I'm kind of splitting the different between the opinions of Matt O. and Chris C.--I think it's obvious that Carey is capable of being more polished, and is choosing (assuming it's entirely his choice) not to be. But I don't think that we have therefore seen all the improvement we're gonna see. Even if he doesn't stick to a script, playing the games more and more can only make him more and more comfortable with the rules. Just to give one example, he's gotten much better at explaining Grocery Game, telling the contestant very clearly that they can buy more than one set of products to reach $20-21, and that the total is cumulative.
For some of the other things mentioned: I actually don't have much of a problem with his showcase reveals. Yeah, he dropped the ball on the MDSes, and he does occasionally take too long to acknowledge the winner, but I don't mind him slipping in a "sorry, man, you were close" before congratulating the winner.
And . . . considering all of this examination of Carey's loose style, I find it very weird that he always says "here's how to get a ticket if you want one" without so much as a syllable out of place. The only explanation I have is that Drew thinks it's silly that anyone in 2008 who is interested enough in TPIR to want to be in the audience doesn't already know the procedure. I mean, considering the way he treats the rest of the show, he surely can't be uninterested in having people show up for tapings.
(I should mention that all of this doesn't mean I think that Drew Carey's work on the show merits an A+. He does have other habits that drive me up the wall, like saying someone's name 20 times in 3 seconds when he's trying to get their attention.)