When I reviewed Dirt 2 a year and a half ago I found myself truly impressed with the number of cars, tracks, drivers, race types, etc. present in the game. If cars weren't quite as customizable as I may have liked, they were incredibly fun to drive, and even if the home base was a little under-realized, it did what was necessary. The new Dirt 3 takes everything from Dirt 2 and builds upon it in deliberate, but not always better, fashion.
Whoa there, rein in the horses, you've probably read that the new Dirt is fandiddliantastic with even more of what made the last one great (and the last one was great). Consequently, you're instantly unhappy with my saying that the new one isn't always better. Just understand what I'm actually really saying – every change made feels like a purposeful one and while the result is another great game, not every decision made was a good one. Dirt 3 is great, but after playing it I can't help but feel that it could have been better.
I will be the first to admit that I was not wholly and completely in love with the magical trailer that would follow you all over the world in Dirt 2. It was something of a silly way of organizing all the important career mode aspects in a single place. For Dirt 3, Codemasters has eliminated the trailer. The result of this is a less cohesive, less complete feeling career mode. There is certainly more to do in the mode, but without a single cohesive hub to show you what you have done and what's left, the game loses something. You're just racing here, you're not building a substantive career.
There is a logic to this decision, in Dirt 2 you were working your way up the ladder from novice to professional driver, in Dirt 3, you're starting off as a pro. Things still get harder as you go, but the point of career mode is just to win every race and unlock everything you possibly can, not to work your way up any ladder. But, whatever the reasons may have been, a more focused central hub for career mode would have been beneficial to the title.