I currently use 2 water bottles. However, I'm thinking about purchasing a camelback (sp?) I drink a lot of water during the summer, especially july and august. Sometimes 2 bottles isn't enough water. I've tried carrying extra bottles in my pockets on my Jerseys, but I find that uncomfortable.
I don't like wearing a backpack either. So, I probably wouldn't like a camelback. But I may give it a try.