I didn't care for My Fitness Pal although I know a lot of people who love them.
I currently use Lose It, mostly the app on my iphone but they have a full site as well.
I also really like Map My Fitness and Sparkpeople. I think Sparkpeople was the most user friendly and had lots of fun community boards, groups, challenges etc.
Maybe I should try MFP again. I only tried the app but preferred Lose It.