Hmm... 927 ml for the X360, 896 ml for the PS3. And this according to vgchartz, which isn't exactly reliable and it doesn't include the digital sales. That are supposed to be higher in the console that launched with an internal HDD simply because it could store the digital games since launch.
I wouldn't be surprised if the PS3 is winning against the X360 even there. And this launching 1 - 1/2 year later.







