im sure many people will disagree but i have read many official articles from independent testers and developers and apparently there is nothing between them.if anything,the 360 looks better at this stage running the same games as the ps3.the deciding factor for you,however,should not be based on graphics but whether the ps3 has exclusive titles that you cannot do without...but this list is getting shorter all the time.
I had the same dilema, I have decided to enjoy my 360 and let the launch of the PS3 pass me by,none of the launch titles are making me jealous.
Later in the year maybe when games companies have got the hang of programming the PS3 will games emerge making me want one.
I have read the same reports as Mattk. I dont think there is going to be much between them. Its down to exclusive titles and if its worth spending 600 quid to play them (thats a lot of Xbox 360 games!) Latest rumours are that Metal Gear Solid 4 should be coming to Xbox360