Aside from the fact the C seat is much nicer...

I took the 8:30 a.m. 777 flight IAD-DEN last week, and we were served a very adequate hot breakfast: eggs, potatoes, bacon, sausage, side fruit plate, and danish. I think the other choice was probably the fruit plate with yogurt.

Larger (and more experienced ) cabin crew, more lavs, personal TV, more movies, etc. If you have the choice, the 777 is the clear winner.