How popular is Killzone 3

I currently own KillZone 3, and there is a large online community. Sometimes there are too many players online to be able to play a certain game type, thus I believe that the game is quite popular.
KillZone 3 has a campaign that runs about 4 hours long, on the recruit setting.
The online is also quite good, with lots of customizability and upgrades. I would definitely get this game if I were you.