I've tried iChange and SparkPeople, ultimately rejecting both because I get REALLY frustrated when things are hard to change. Also, I have no need for another support community outside 3FC!
So that's two weeks of calorie tracking now lost on those sites. Ah well. I've transferred to LoseIt and I actually like it a lot -- very simple & intuitive, great charts, and most of all *extremely* efficient nutrient-input interface. It doesn't track random vitamins, though, so if you're watching random things like that, or need support, it's not so great. But basically every basic & restaurant food is on their database, so I have no complaints.