Well I initially bought the 360 when the GTA4 came out, along with with a few games i had my eye on, like Mass effect, then just before Christmas i got my PS3 for MGS4.
Though both consoles do have similar games, there are few exclusives released and yet to be released that are worth owning the systems for. I haven't really looked into whats coming out for the 2 systems in 2009 as of yet, but i am really looking forward to Heavy Rain and Alan Wake. 
Nintendo & Sony Supporter
Currently own- DS, PSP, PS2, Wii, Xbox 360, PS3 DreamCast.
Man i have too many consoles.....
Quotes to live by!
"Life is either a daring adventure or nothing"- Helen Keller
"i am not discouraged, because every wrong attempt discarded is another step forward"-Thomas Edison
"Man is not the creature of circumstances. Circumstances are the creatures of men"
