Salam fellow PWers! 
Here goes a small effort of mine for a comparison between the Honda Civic 8th gen and the 9th gen. The pictorial differences are already obvious though, won't be going to them. Instead, I'll just share my own experience, the driving feel and the differences between the cars that can't actually be explained by pictures. Some practical observations you can say.
When the 8th gen was launched, it was a big upgrade and enhancement in almost every single aspect than the old 7th gen. The looks, size, engine, transmission, interior, exterior, everything seemed like a NEW civic altogether. Nothing resembled like the old one. Even an uneducated person could tell the difference and praised it as a LOT better.
Though, this isn't the case when it comes to 9th gen civic. People haven't been praising it, over 95% of the people are actually preferring 8th gen over 9th gen. But I must say, for a person who has been used to 8th gen in terms of daily driven vehicles, its a really significant upgrade.
My observation is based on a comparison vs Oriel manual 8th gen and Oriel Prosmatec 9th gen; somewhat an "odd" couple of trims as people may say, but to me, it feels quite ok if one has to judge the drive, ride quality and significant improvements over the time. I have tried to cover almost everything, wasn't easy to distribute the information under different headings, but still I did try, I hope its not as difficult to understand as I think.
Ride Quality/Drive experience:
The ride quality, driving experience, the stability etc is very much different than the 8th generation. The suspension is quite a lot softer, the ride feeling is leaned towards the family sedan concept rather than the sportiness, the characteristic honda civic drive. I drove it on motorway, at speeds exceeding 170-180kph, on stock eurostars, the stability was impressive. Comparing it to the 8th gen's factor, its stability I don't consider questionable owing to the factor of a hard suspension system.
Its more like a sweet combination of sport and comfort. At crusing speeds of 100-120kph, the car feels as smooth as it could ever be. No uncomfortable feelings at all even on the roads having worst cover of tar and potholes. 8th gen civic felt uncomfortable to me at those roads, esp in my hometown area, @ahmadbila knows what I am talking about.
Also, I am used to travelling in the 8th gen since quite a while now, and I always feel tired after a journey of 3-4 hours. The roads aren't driver friendly here. But kust as I felt fresh after the same drive in a friends altis, it was a refreshing experience on the 9th gen as well. Probably cz of the excitement (lol) but I think the suspension is a great improvement, an overhaul.
Engine/Power-train:
Coming to the engine, as we all know, the engine hasn't been changed over the generation. Its the same 1799cc R18a iVTEC motor. Therefore the power remains almost the same. Power/weight ratio isn't much different either. However, the prosmatec 9th gen I drove gave me a very clear and obvious idea of one good change over the time, and thats the reduced transmission lags. I dont really know the technical values, its just a clear observation off my experience with both. Gear ratios are essentially the same, in both manual and prosmatec, nothing is changed as such. But the feel when you floor a 9th gen civic is totally different. Its much MORE responsive at low rpms, the ivtec function disengages more swiftly and delivers power in lesser time than the 8th gen, i.e, if you need to escape a situation or you need to take panga (
), just floor it and you won't notice it crossing the speeds of 130-140kph, simply effortless.
I experienced a few friendly runs with 8th gen oriel manual and 9th gen oriel prosmatec, I must say, unless there is a very experienced swift shifter behind the 8th gen's wheel, the 9th gen keeps the run neck to neck at almost all speeds, at least thats what I saw upto 160kph on a normal road, not motorway.
Fuel economy:
The most important part, fuel economy. Its obvious, 9th gen's comparison vs the 8th gen in terms of that isn't quite justified.
Despite being a prosmatec, the 9th gen delivered a lot better mileage figures than the 8th gen. The part that I loved the most was the fact that 9th gen's mileage figures actually vary with driving styles. With the 8th gen, varying driving styles wasn't much of a technique to improve the mileage.
The motor has been tweaked such has to behave like a gas guzzler at speeds and high rpms (bombastic driving in short) and to serve as an economy vehicle with smooth, balanced driving.
If the 8th gen was driven anything above 120, the mileage figurs would always be around 11-13kpl, nothing more than that. but if the 9th gen is driven, lets say at a constant speed of 120kph, its possible to acheive more than 15-16kpl on a prosmatec transmission without much hassle of hypermiling. Econ is a very nice feature, its one of the big highlights serving as a reason for the 8th-9th upgrade.
Braking:
Braking, in the 8th gen civic era, it was probably the best stock braking system that was equipped in the car. Nothing braked like an 8th gen civic. For the 9th gen, the braking is very well up to the mark even with crap eurostars. I had a few close encounters in one of the most pathetic driving conditions in Pakistan and the braking served very well.
One thing I did notice was the sound of ABS kicking in. The 8th gen civic sound could be heard like a significant "grr grr grr" but in he 9th gen, its HARDLY even noticeable as a noise. A regular driver would need a lot of keen observation to notice the system coming into play.
Cabin Noise:
Cabin noise, this is the thing I loved a lot about the 9th gen. The engine revving above 4k rpms on a highway is a lot quiter than the 8th gen. Loved it. When pushed above 170 kph, there was only a slight sound of vroom inside the cabin and the song that played from the stock audio was still enjoyable.
Road Clearance:
The road clearance of the 9th gen is to die for, esp after one has experienced an 8th gen as a family sedan. I drove it with 5 people, it felt totally perfect, didn't bother touching any of the normally designed speed breakers. For the oddly placed ones, like designed by sheeda mochi in front of his shop etc, its a different case though.
Visibility; Day/Night:
The visibilty has been improved a lot. The corners, pillar blind spots etc have minimized significantly, thanks to the bigger pillar glasses. The car feels a bit compact than the 8th gen when driving through dense traffic, more like a honda city.
For the night, well I must say that projector lamps serve a lot in nght driving, headlight visibilty range is better than normal parabolic lamps. The cut off is sharp, even when used with HIDs, functions excellent.
The interior:
Yes writing specially about this thing, the interior is a lot classier than the 8th gen civic. Feels a bit too cozy though, but its the way its styled to be. Doesn't feel odd at all. After being in a 9th gen, almost every other PKDM car of this class feels primitive. I like it. <3
A few things which I missed and disliked:
The only thing I missed A LOT in the 9th gen was the organ type accelerator pedal. It was very comfortable feature, you could rest your foot on it for prolonged periods of time without feeling itchy and tucky. The 9th gen gas pedal is once again downgraded to a simple one 
The dual tip exhaust is also something to be missed.
The rear reading lights are also gone.
Below the climate control buttons, in front of the shift lever, there is around 3 or four square inches of blank space, looked very odd to me.
Looks (a side note):
The only thing that has been criticised a lot about this car is its looks. Esp the exterior. The lifted rear end which resembles the pre-facelift 5th generation honda city. Well, for that I must say, it isn't much of an excuse. After what you're getting in that price tag, looks is the last thing which matters. Especially in Pakistan, where you have ONLY two cars: civic vs altis.
And its something which is gonna fit in your eyes after all. Apni har cheez hoobsoorat lagti hai bhai.
I remember a brother syaing k "6 saal poraani shape se bore nahi huay?" and there was one who said "gari dekhni to doosron ne hoti hai, aapko konsi dikh rahi hoti hai when driving?" :P
Conclusion:
The 9th gen is an improved vehicle in almost every aspect that matters over its predecessor. Fuel economy, suspension, comfort, features etc; I can't actually think of any reason of NOT upgrading if budget isn't an issue.
I recommend go for it if you have the $$$ and want a change. Its well worth its price tag and will be keeping you happy.
P.S Apologies for the mistakes (if any). Its late and I am sleepy.
Comments welcomed, correct me if I wrote something wrong here, do keep in mind the fact that all of this was my PERSONAL observation and opinion. Nothing technical or bookish has been implied.
