I played tonight and occassionaly saw the AI cars running each other off the road. Yeah, it was mostly targeted at me, but the game would be a little boring if it wasn't :)
Timing your drifts around the corners is crucial, as Monstermile pointed out. It's a big change from PGR2, that's for sure! Normally, I'd take the outside lane and cut into the inside on the turns, but in BO3, try staying in the inside, tap the brake about a car-length from the corner, then accelerate around the corner, and finally turn away from the turn to straighten back up. Just don't oversteer as you come out of the turn or you will fail to come out of the drift (obviously) and lose control. Once you get the timing right, you will sail around corners and rack up some nice drift points. If traffic permits, stay in the drift as long as you can for more points.
As for technical issues, I've had a bunch of them, but only on Xbox Live. I was playing with a group of 5 other people, and we all have experienced total game freezes, disconnects, invites not showing up, and not able to join games. The online part of this game is extremely glitchy at this point. Perhaps this will settle down after EA gets a handle on all the traffic on their servers (or fixes bugs). This seems to be pretty common. I've heard there were issues with both Madden and NCAA Football on Live, and I know ESPN has problems with their Live servers too. Their's seems to be caused by Microsoft's new Live Server Platform, which appears to have some security gateway issues.
Oh well, single player mode is what I've always enjoyed in the past. Guess I'll just have to be patient for decent Live play from this game. *sigh*