360 and PS3 are more or less neck and neck, time adjusted, for HW.
For SW 360 definitely sells a bit more. This is down to two factors so far as I can see:
1 - MS has pushed out more versions of high selling franchises vs Sony (on PS3 there has been one full GT and one minor GT release, plus 3 Uncharted titles in terms of big selling exclusives, plus 1 God of War and 1 MGS. MS has pushed out 3 Halo titles, plus 3 Gears titles, plus 2 Forza titles, etc in the same time frame. Sony has pushed out more exclusives overall but one Reach can easily sell the same as four mid range exclusives on PS3. MS stategy isn't so good for game diversity for the player but makes sense in terms of unit sales - it's basically down to do you release 1 Avatar film vs 4 solid and very different films in different genres?)
2 - MS is dominant in two of the regions with the highest purchase rate for games for consoles (so far as I am aware) with the US and UK. These regions are also huge for online FPS/action titles so 360 almost always sees a nice additional boost over PS3 unit sales for key third party titles - given how often CoD titles have releases, selling more of these soon adds up for example).
None of this means PS3 is bad or 360 in itself as a console is magically better, its just down to different strategies for core exclusives and which regions they are dominant in. Personally I'd rather play/watch more stuff than one big title but that's just personal preference. Doesn't make MS strategy wrong and strictly speaking from a unit volume/profit perspective MS strategy makes sense.
Both have sold a lot of SW though and I suspect both will sell a lot more. Each also has a pretty strong attach ratio although 360s should remain ahead unless it sees a sudden drop in big sellers next to PS3 (which could happen I suppose but I suspect MS will remain on point to prevent that. We know at least one more Halo, for example, will launch on 360).
.