I know some of you have had issues with the AI but I have to say I have only had ocassional issues with it. It's certainly better than AI cars I have played anywhere else.
I believe some improvements to AI have to be done on a track by track and car by car basis so it takes a lot of time to test/get right. I don't believe it is either "broken" or "fixed" but it has to slowly evolve. So I'm guessing improvement will only come bit by bit on that front.
It's the best offline experience I've had with any game. That is from offline quick race mode which is generally excellent. I haven't done much career yet as I'm letting you lot test that
What I have tried in the karts has been cery good.
As for online I've had some excellent racing in private rooms. I made the effort to friend as many people as possible on GTPlanet as well as having quite a few friends/club members also get the game. It definitely makes a difference to the quality and quantity of rooms I have run or joined. As an example we had some great racing running RUF Super Cup races on Friday night. A nearly full private room supplimented by a few AI. Unfortunately one of those AI drivers, we'll refer to as "Carlos", had escaped from an institute for the criminally insane but he gave us a laugh for 25 minutes as we all tried to avoid him at Zhuhai. We just needed a kick Carlos button for the race. Online has actually given me the most enjoyable racing experiences I've had in any of my long years searching for the "one" racing game since I started playing Pocketeers in the 70's. Im certain I've found it but we all probably need a bit more patience before it will please most of us.
Bugs etc are there of course but I don't come across them that often and they really aren't as prevalent as they might appear to be from reading some threads here and on the official forums where of course we read about them all lumped together.
The game has crashed on me a couple of times in 50 hours of play. I think that's pretty fair for a new game. Obviously some have had that happen more often but I can only speak about my experience.