I started gaming back in 1984 when I got a Commodore 64. From then on I've gone through all the generations, Sega Master System, Mega Drive, Mega CD, Dreamcast! Nintendo NES, SNES, 64, Gamecube, Playstation 1, 2 blah blah blah.
There are, at the moment, 3 consoles on the market.
The Xbox 360 is the oldest now but still maintains the biggest following and still out ranks the other two in my opinion.
The Wii, for me, is aimed towards a younger audience and to those who don't usually play games. It's very family orientated. Not a bad thing at all but for gamers it just doesn't compare.

The PS3 on the other hand is a different kettle of fish all together. With it's Blu Ray player and far superior hardware it's the next generation console that ticks all the buttons. So why does the Xbox still come out on top?
Simply it comes down to price. For most people it's hard to justify paying an extra £100-ish for a Blu Ray player that will cost around £20 to buy movies for.
the online community on the xbox and the interaction with friends is far easier and more reliable than the Playstation network. OK so the PS network is free while it's about £35 a year for the Microsoft one, but it's worth paying for. You get far more options and far better reliability with Microsoft's Xbox network simply because you are paying for it!
There are more games on the Xbox and with almost all of them offering additional downloadable content that you can't get on teh PS3 it just adds to the increasing list of reasons to get the Xbox over the PS3.
The graphics are pretty much the same. yes the PS3 does have slightly better graphics but not so noticable to you and me.

In a nutshell apart from the Blu Ray player and the cost of the online subscription it beats the PS3 on so many levels.
More games, better online community, HD graphics, downloadable content meaning your games last longer, multimedia connectivity (connect to your PC and stream films - really easy!).
Get an Xbox now, wait 4 years then get the new Xbox. Save your money and stay away from Sony, unless you can afford an extra £100 and dont mind having less choice of games etc.