In an odd way the apparent lack of GTA4 "booster sales" shores up my own theory that yes, the single-uber megahit console selling title is mostly a myth, in most cases, but this applies backwards in history: the Gamecube did not do as well as hoped in software sales for big titles not because Wind Waker, Mario Sunshine, etc, are the worst games ever or disappointment-tons (no matter what prickly, petty hardcore gripe about) but because the system itself was not as widely and quickly embraced as prior Nintendo consoles.
In short, if people already had the console, they'd be more likely to buy the big titles over everything else, but if they didn't have the console, even a top end Mario or Zelda (or GTA, etc) game is not enough to sway most of them by itself. One thing the hardcore often don't seem to grasp is that even people only slightly less devoted (obsessed) than themselves, people for whom videogaming is not their centerpiece, primary hobby, even if they play games a lot, are not nearly as likely to rush out and buy a $200-$300 dollar console for just 1 - 3 great games.
Wii is enjoying greater sales for core, traditional gaming titles overall, because more people are buying it faster, not necessarily because those titles are simply a billion times better than prior entries or any other games out there. (Though I do think on the whole, Nintendo's Wii era entries in their core series are either as good as, or significantly better than, the previous pinnacle titles in each series, with the exception of Super Paper Mario, which is good, but not nearly on the level of The Thousand Year Door.)
Having said that, I basically agree with the Wonder Rant upthread to the effect that at this point people are in total denial when trying to squeal that Wii is not a "real" console or that we're not witnessing a sea change in gaming rather than a fluke caused by somebody "selling out" for temporary success to a perceived casual gamer market. I personally know perhaps 30 dedicated, geeky, hardcore lifelong gamers, most of those, I know offline as well as Internet Personalities. Of those 30, about 25 bought a Wii. Of the remaining 5, the other 4 haven't found one yet, and 1 is a sourpuss who pretty much lives up to the stereotype of desiring only to run down hookers in stolen cars, and relive WWII yet again. And even he doesn't particularly hate Nintendo or work himself up into these hardcore hysterics over the Fall of Gaming.
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