PS3 won't overtake 360 this year, unless it plans to sell double/triple the 360's amount each and every week, it's just ahead each week as it is.
I'd say it'll overtake in mid-late 09, if not then, definitely by 2010.
I highly doubt PS3 will sell 11 million this year. I'd say that 8-9 million per year is a reasonable figure for PS3 sales, but even then if microsoft continues to hit 7 million a year, PS3 taking over will be a while away.