Opinions on upgrade options

[CleanSlate]

Hey guys, I thought I'd ask for opinions on upgrading my system and if now is even the time.

Current Specs:
All items at stock settings

AMD x6 1100t
msi 890fxa-gd65 motherboard (is this AM3+ compatible? I can't find that spec anywhere)
2x4 - 8 gigs of ddr3 ram CL7 (forget the brand)
ATi 4890 1 gig gddr5
Main HD: 64 gig Patriot TORQX TRB SSD
Gaming HD: Hitachi 2TB HD with 64 meg buffer
Antec 650 watt psu

I'm wondering if I should upgrade my cpu vs upgrading my gpu for 1080p 2x/2x gaming (AA and AF are not really important to me). I have been kind of teetering between the two.

For instance I play Alien Swarm which is only laggy during extreme swarm times and during specific bad points on the map- I would like this game to run smoothly no matter the situation because the lag can be a killer.

I will also be playing BF3 later, I play CSS some times, star craft 2 some day, bad company 2 and skyrim but skyrim runs well enough on this system.

Thanks for any advice in advance.

 

[Dangman]

Go for a GPU upgrade. Wait for the AMD HD 7xxx series to come out and grab one of those cards then.

 

[Outamyhead]

Yeah system seems to look good, just that graphics card sticks out like a sore thumb as your problem in game performance.