If you have ESPN Insider, go check out Buster Olney's blog for a Q&A with Kevin Millar. Since it's a pay feature (and also since it's ESPN), I can only provide a couple snippets to entice you, the reader, but let me cherry-pick a couple of the more interesting quotes from Millar.
His future is very bright. The guy has a tremendous eye for the strike zone for such a young player, and he handles the breaking ball very well. He also never gets too down or too high with his struggles or his success, and he had both struggles and success his rookie year. He'll be a fine player for years to come if healthy.
On his rep as a good clubhouse guy:
I have never liked cliques on a ball club. I feel a team is your family. You spend more time with your teammates more than your family for seven months. You shower, eat together, and battle together. If you can get all the guys pulling for each other and caring for each other it makes it a lot easier to battle. Winning teams have that. You don't have to be the best player position by position, but you have to care about your teammates and pull for them. I'm not the best player, but I do my best to have positive energy and keep things loose through the tough times.