I'd go try out the boots first, buy the ones that fit and feel the best and THEN see how much was left for the board/bindings. Buy a 2011 carbon credit and you'll have another 80 bucks for the boots right there
edit: when I started boarding not long ago, I bought everything based on how much it cost.. With emphasis on the board. Well, after much pain and suffering with my boots, I decided to do the right thing and go buy some good fitting boots. The difference it made with my riding, both in ability, comfort and how long I was able to ride for in a day, was incredible. I have trouble believing that any board would make up for shitty boots!
edit2: You know what.. I don't even know what boots I ride! I know they're DC boots, with the Boa thingy, and they're white. But I have no idea what the model is, they're just the ones that fit me!
If you are going to buy anything in person it should be the boots. Every single person I have talked to has told me this. I went in the other day to try on boots and find out my boot size. It was the best thing I could have done. Being able to feel all the boots and see them in person is 100 times better than buying boots online.