4
More than ps3
Yes, there are many people who play FEAR 3 online on Xbox 360.
There are about 23 million ONLINE Xbox users. The total amount of ALL the Xbox users is unknown.
1-8
i dont think many people play halo 2 pc, but alot of people play halo 2 xbox with xbox live!
less than the 360
Yes you can. I saw that its better than playing it on the xbox. But multiplayer is a little hard to get for many people.
There is no way. PS3 users play on "PlayStation Network". XBox users play on "XBox Live".
No
You can play many regular Xbox games on the Xbox 360.
You can play it while signed into xbox live, but you cant play with other people through xbox live on oblivion.