According to NPD both the Xbox 360 and PS3 have passed the Wii in America YTD software by revenue.

Starting at the bottom, the venerable PlayStation 2 has seen its YTD software revenue drop by 70%, which is not that unexpected for a system which just completed ten years in the U.S. market.
The PSP, which has been on the market for over five and a half years, also saw a dramatic decline (over 30%) in its software revenue so far this year. Its slower fall has put it ahead of the PS2 in terms of revenue this year, but it still accounts for less than 3% of the software market, by our estimates.
Software revenue on Nintendo's DS platform, which this month begins its seventh year on the market, dropped by a somewhat more modest 12% from 2009 to 2010. Still, it accounts for nearly 1 in ever 7 software dollars spent so far this year.
The top three software revenue generators are the current-generation consoles, and here is where things get interesting. In October 2009, the Wii had generated the most software revenue of any single system on the market, just slightly ahead of the Xbox 360.
However, at this point in 2010 it is third, behind the PlayStation 3.
In contrast, the Xbox 360 has nudged its revenue up over 8%, helped in great part by sales of Halo: Reach in September and October. The PlayStation 3 has done even better, relatively speaking, with software revenue going up by over 25%.
These figure are even more striking when one considers the installed hardware bases. The Nintendo Wii has passed the 30.5 million system mark, or over 2.2 times the size of the PS3 installed base of 13.7 million systems.
With that kind of advantage, it is notable that the PS3 has moved approximately $100 million more software this year than has the Wii. Simply put, the average PS3 owner is spending significantly more money on software than is the average Wii owner.
Note, however, that this does not mean that the PS3 is selling more units of software – just that it is generating more revenue. Due to the differential in average software prices for each of the platforms, the Wii undoubtedly has moved more units of software in 2010, but more money has been spent on PS3 software.
To sum up our first look at software revenue: the three oldest systems on the market along with the Wii are all seeing declines in software revenue (down 27% or about $840 million), while the Xbox 360 and PS3 are showing increases (up 16% or about $440 million).
If we group platforms by manufacturer, we get another view of software revenue, shown below.

Since Microsoft has only the one platform, the Xbox 360, the story we see here is the same: over $100 million in software revenue growth.
For Sony, the so-called PlayStation family of systems has realized a small, approximately $20 million, decline in software revenue. The company has at last generated enough demand with its flagship console to overcome almost all of the software losses its is experiencing on the PS2 and PSP.
However, these systems appear to be on terminal trajectories, and if their revenues effectively go to zero in 2011 then the question becomes whether the PS3 can fill that gap – about $450 million – in Sony's revenue stream.
The larger story in the figure above, however, is the $500 million contraction in software revenue on Nintendo's platforms. Industry-wide, retail video game software revenue has fallen only $400 million, and Nintendo's systems have contributed all of that loss and more. If it weren't for strong Xbox 360 software revenue this year, the industry's hole would be even deeper.
Source: http://www.gamasutra.com/view/feature/6210/npd_behind_the_numbers_october_.php?page=2
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