Most people would agree with you.  I'm one of the few who expects a major fall in GTA sales this generation.  I expect at least a 25% drop, and more likely a 33% or more drop, because of the loss of the casual audience.

Here are my thoughts. But basically they reflect the same as what everyone else as said. In other words, if you throw out the DS games and the pack-in/packaged Wii titles, there is a very short list of games that could exceed the 17M predicted.

List is below.

1. Wii Sports 18.52M
-- YES but pack in in NA and EU
2. Nintendogs 17.35M
-- YES but DS
3. Pokemon Diamond/Pearl 13.65M
-- YES but DS
4. New Super Mario Bros. 13.16M
-- Maybe (also DS) and old and don't know its legs
5. Brain Training 11.69M Maybe (also DS)
-- MAYBE (also DS) also old and don't know its legs
6. More Brain Training 9.85M
-- MAYBE (also DS) also old and don't know its legs
7. Wii Play 9.70M
-- YES but packed wth controller
8. Mario Kart DS 9.45M
-- MAYBE (also DS) also old and don't know its legs
9. Animal Crossing: Wild World 8.90M
-- MAYBE (also DS) also old and don't know its legs
10. Super Mario Galaxy 5.54M
-- MAYBE as it has good legs. SSMB and SMG could compete for top selling non-pack-in/packaged console game of this generation
11. Wii Fit 1.28M
-- DOUBTFUL as cost will limit widespread purchase
12. Mario Kart Wii
-- DOUBTFUL as SSB more popular than Kart
Animal Crossing Wii
-- DOUBTFUL as SSB more popular than AC
Grand Theft Auto IV 360
-- DOUBTFUL as 360 does not have PS2 base and Brawl predicted to sell more than any previous GTA game
Subsequent GTA games for any home system
-- DOUBTFUL as 360 or PS3 does not have PS2 base and Brawl predicted to sell more than any previous GT A game
Halo 3 7.13M
-- DOUBTFUL as game is old and does not have stong legs (will be passed by SMG sometime this summer) and 360 sales have stalled
Gran Turismo 5
-- DOUBTFUL as PS3 does not have PS2 base and Brawl predicted to sell more than any previous Grand Turismo game
Subsequent Brain Training games for DS or Wii
-- MAYBE
Subsequent Nintendogs games for DS or Wii
-- DOUBTFUL
Wii Music
-- DOUBTFUL as cost (keyboard) could limit widespread purchase
Other as-of-yet-unknown Wii brand games
-- HUH?
Other unknown game(s)
-- HUH?

Mike from Morgantown

Maybe among our repressed and ignorant gaming community yes.... but if that hype will still not outsell Mario Kart.

a lot of those games are either pack-ins or DS games. the only games that have a shot at ssbb this gen on consoles (not multi-plat) are other wii games. and those games are probably limited to wii fit, smg, and mario kart. but i think it likely ssbb will prevail over them.

if you wanna talk multi-plat games for consoles then there is gta4 and COD4. but i see COD4 ending up around no higher than 10 million between both systems and gta4 maybe 10-13 million and ssbb will certainly sell more than that most likely along with the other wii games mentioned above. other than halo 3 which might grab 5th no game thats exclusive to 360 or ps3 has a shot in hell at the top 5 this gen (out of exclusives only of course since normally when comparing game sales you compare by single systems and not across several platforms.)

mike_intellivision did a very good analysis.

 y not? MKDD only outsold Melee by 20,000 units.

It doesn't have to be the biggest selling game this gen to get 20 million. ;^)

maby the top three will outsell brawl, but brawl will be big

Brawl exceed every game this generation except Wii sports, Wii play and Maybe Wii Fit.

Wow, some of this optimism is funny. More than 15 mil is a big strech. It'll be over 10, but will fall short of GTA:SA sales.

why do you guys even care how much a game sells.. just buy it if you want and stop judging a game´s success depending on its sales.