From the bits I saw and read about him in Iowa, he seemed quite good.

He made fun of the Senate, describing what it did over the weekend this way:

Our majority leader, the senator from Nevada, called the Senate into session on Saturday and let me tell you what we voted on — so that we could debate a cloture vote to cut off debate on a motion to proceed to another cloture vote to cut off debate about a meaningless resolution. That was your tax dollars of work, my friends, last Saturday.

He made it clear that he opposes Roe v. Wade: “I do not support Roe versus Wade. It should be overturned.” (Would that Rudy would say the same.)

He visited an abstinence program. (If Rudy’s going to run as a pro-choicer, the least he can do is be very forthright against out-of-wedlock child-bearing and teen sex, but he might want to avoid the topic of sexual mores altogether.)

He let loose on Rumsfeld and apparently got a positive reaction: “I think that Donald Rumsfeld will go down in history as one of the worst secretaries of defense in history,” McCain said to applause.

Roger Simon wrote this:

And, at the end of a long campaign day, when I found myself in an elevator with him in the Radisson Hotel in Davenport, Iowa, I mentioned to him that his appearances seemed to get stronger as the day went on.
He agreed and said that was because he was finding his groove once again.

One thing that was clear from McCain’s 2000 run is that he can be fantastic on the stump. The problem with that campaign was not McCain’s performance per se, but its strategic mis-positioning.