Wii has the clear inside track, right now they are essentially tied, but Wii will scale up higher in the coming months than PS3, as ioi points out, PS3 has really one game left to drive sales, FF13, but that's a one week boost, not to mention expected sales will be low for an FF game, on the other hand Wii has a stronger lineup and a bigger crowning game in NSMB.
Predictions:Sales of Wii Fit will surpass the combined sales of the Grand Theft Auto franchiseLifetime sales of Wii will surpass the combined sales of the entire Playstation family of consoles by 12/31/2015 Wii hardware sales will surpass the total hardware sales of the PS2 by 12/31/2010 Wii will have 50% marketshare or more by the end of 2008 (I was wrong!! It was a little over 48% only)Wii will surpass 45 Million in lifetime sales by the end of 2008 (I was wrong!! Nintendo Financials showed it fell slightly short of 45 million shipped by end of 2008)Wii will surpass 80 Million in lifetime sales by the end of 2009 (I was wrong!! Wii didn't even get to 70 Million)