It is a giant game of quake basically..
Definitely has its appeals, and its addiction however it doesn't have the depth that most MMORPG's have(hence it being an MMOFPS)..
There are VERY limited skills, you don't really build your character as far as skill points go, so there is really nothing to work towards.
If you want a game with scope and complexity that plays like a true MMORPG except for with a first person shoot em up feel
Neocron is your best bet
PLUS Neocron is also releasing its free download trial version on the second of may.. So you can download it, play it for free for 7 days and then if you aren't addicted like a whore to crack just cancel..