Not only is it stretching the truth, it isn't even true at all. Amazon's 2009 video game-related sales charts show they sold more Wii games then any other console, and by a wide margin, with nearly twice as many Wii games in the top 100 then the PS3, and quite a bit more then double what the 360 has (there's a shocker, though the 360 does have some higher placers then the PS3). And the Wii has the top spots. The highest selling game for the year was NSMBWii. In fact there is only 1 360 or PS3 game in the top ten, and that being at spot 9 (Call of Duty: MW2 360). The Wii blew away the other consoles not only in terms of console and hardware sales, but in software sales.
http://www.amazon.com/gp/bestsellers/2009/videogames/
Also, going back month-to-month, the Wii had the highest selling game in all but 3 months of the year. The 360 had a lowly 2 months at the top spot (COD:MW2 and Halo ODST), and The Sims 3 had it for one month.
So, enough with these bogus reports about poor Wii game sales. Now, if you want to limit it to only M rated titles, yes, the 360 and PS3 blow the doors off the Wii.
EDIT: and January isn't starting out too well for the PS3 and 360. So far for January the Wii is outselling (talking about games), the other consoles by a huge margin. The first PS3 or 360 game is found way down in spot 16, being God of War Collection for PS3. The Wii has 9 games above that and the rest is Wii consoles and accessories with the exception of the 12 month Gold membership which is actually at spot 1 currentlty! No wonder Microsoft likes to make you pay for online play. It's looking to be one of the few things that sells for the 360. In terms of games, they are currently down at spot 18, with one of the few 360 games that sells well, Call of Duty MW2.