In my flat now there are six of us, three girls and three boys. It's really more like four of us though since we have two international students who we never see (not even sure they eat!) I've yet to speak to the Romanian guy!
I like the number of people. It's enough that it's never too quiet, but not so much that the place is hard to keep clean, or that we have to fight for oven space. However, I next year I'm in an all girls flat of 6. From what I've seen, it's guys that are the messy ones and the noisy ones. Not sure if that's true, just what seems to happen around here! Maybe I'm in for a shock come september!
Over the Easter break