It took less than a year:

http://vgchartz.com/hwcomps.php?cons1=Wii&reg1=All&cons2=PS3&reg2=All&cons3=X360&reg3=All&start=39040&end=39327&weekly=1

But that is because the Wii was routinely selling close to 200,000 more units per week:

http://vgchartz.com/hwcomps.php?cons1=Wii&reg1=All&cons2=PS3&reg2=All&cons3=X360&reg3=All&start=39040&end=39327

Look at the chart.  Find how much more you think that the PS3 will sell over the 360 on average each week.  It will then tell you how many weeks it will take to catch the 360.

Personally, I think this gen will be pretty much over in around 3 to 3.5 years.  That means to catch the 360, the PS3 will have to sell between 44,000 and 51,000 units more than the 360.  I don't see that happening.  Even if it did, that would basically be a tie, and wouldn't change anything in the market.

For any meaningful change in the market to occur, the PS3 would have to pass the 360 in the next year or two.  That would mean that the PS3 would have to outsell the 360 by 76,000 to 153,0000 units per week.  I really don't see that happening.

hey I didn't even mention SMW I was just too lazy to cut it :P

christmas can do wonders.

even if does 360 will get replaced first. first to come. first to leave.

Once a new gen starts, its game over.  It doesn't matter if the PS3 passes the 360 after that.

Yea, keep saying that to yourself. If by some miracle  Xbox outsells PS2 or GBA outsells PS2, people would made that news bigger than moon landing.

Yep the only console that will be "game over" for when the 720 comes out will be the 360.

Hmmmm

There is a profound difference in outselling a generational competitor after the generation ends (especially if it wasn't even in first place) and outselling sales landmarks of the past.

Had GC outsold Xbox after X360 launched it really wouldn't have meant squat (same scenario as PS3 outselling X360 after X720 releases).  Xbox was just an in generation rival, it wasn't a sales landmark.

^There's no profound difference, because there's no profound sense in the terms you're using.
Outselling as in what? Overtracking? Sales per week? Total sales?
Generation rival as in what? When will this generation end?

They are all conventions, often used in poor data analysis and for use in ego boosting, don't put more semantic weight on their frail shoulders. They can't carry it.

I know a "Wicked Burn" might feel satisfying, but it does not really demonstrate any real understanding of the market or provide any reason why the outcome will be as you predict.

Somewhere in the range of 90% to 95% of all third party games released on the PS3 or XBox 360 are multiplatform games. If you take out the exclusive games where there was some-sort of monetary benefit given by the console manufacturer to develop the game exclusive for their system, it is quite accurate to claim that neither platform can justify much exclusive third party support based on its sales alone.

Certainly, both platforms have big selling games, but when your average game costs $10,000,000 to $20,000,000 to develop and it receives sales in the 333,000 to 666,000 on each platform it is difficult to justify putting it on one platform exclusively. Just because the XBox 360 is replaced by Microsoft doesn’t mean that third party publishers will be able to justify exclusive PS3 support, which means that it is unlikely that support would dry up after Microsoft replaces the XBox 360.

The Wii is in a different boat all together where its low development costs and high userbase really does justify a lot of exclusive and pseudo-exclusive (built from the ground up ports) games; and even if sales begin to decline, it will take years for the entire userbase to move onto something new, which means that it will justify exclusive and pseudo-exclusive games for years after a new generation begins.

When you add this all together, if Microsoft begins a new generation by releasing an advanced system the XBox 360 and PS3 will continue to exist and will (likely) continue to have almost identical game libraries. As the generation goes on the PS3 will be facing competition from new hardware which takes away the selling features that are driving the PS3 today (powerful and advanced hardware), it will face very similar competition at a lower price point (the XBox 360), and it will face competition which has always been more popular and can justify greater residual development based on sales alone (Wii).

In other words, as soon as the next generation begins the PS3 will face competiton in all directions which has noticeable advantages over it. It could quite easily become the "Middle Child" who is easily ignored because it isn't powerful enough, inexpensive enough or popular enough to get the attention of consumers.