It has been a while since I checked in.
I REALLY like www.myfitnesspal.com
there's also www.sparkpeople.com
If you have an iPhone, I recommend Lose It! They have a tandem online site.
I also love Fitday.com, thedailyplate.com, and caloriecount.about.com. :)
MyFitnessPal is great, and it syncs with iPhone/Android/Blackberry. It's very much like the LoseIt! app for the iPhone/iPod touch, but you can access it through a web browser which is really handy. I wish they had better charting/graphing, and more specific nutrient goals, but it's more than decent. My favorite part of MyFitnessPal is that it keeps track of specific nutrients.
CalorieKing.com is a great resource too.