I find that Sony seem to be the all round better buy although hardcore xbox fans will likely disagree with me. I've had an xbox and didn't really agree with it due to the larger controller and having to pay for a half decent online service through Xbox Live. I had it for about 2 years and whilst I did play it always found myself buying the same games on the PS and re-playing them.
If you are a casual gamer I'd probably wait until the PS4 comes out and then buy a PS3. They should drop in price and there will be plenty going cheap on ebay and the likes. That has a blu ray player and the likes of Net Flix and such. Mine has certainly served me well for the last 4 years. From the PS store you should be able to download retro games for about $10 to $15 which would fall in nicely with the likes of Tomb Raider etc.
In comparison to the newer stuff. I'm sure it's impressive but forking our nearly what $450 for a console you'll casually play. To me that doesn't seem worth it.