PS3 + Valkyria Chronicles. i really dont think you would regret it.
By Christmas time I'm sure you could get lots of really big PS3 hits for less than they cost now... and who knows what might come out for Christmas time. but at least by then you would have two systems.
i know your dilemma though, i might be an adult but i'm unemployed so it's a problem. i want the DS XL and i want lots of PS3 games coming out this year.