A console's success can be measured just by units sold (I don't agree with this parameter, but still it's not wrong), but it's a short-sighted comparison. The thing is that Microsoft proved with the X-Box that it can be a viable force in the console market, that it won't just say "Screw you guys, I'm going home" and leave it's system in the gutter if things go bleak. Now when Microsoft releases it's next console people won't see it as the newcomer looking for a quick buck, it'll stand shoulder to shoulder to Sony's next and Nintendo's next. Besides, as noted before, the X-Box wasn't created to generate cash, it was created to show everybody that their comitment to console gaming was serious, so I'd say that the X-Box was a success, and I bet Microsoft thinks the same, it may not have sold well but it sure was successful. Plus, it also showed the developers that it was a viable plataform for their games, so you can bet that 3rd party support won't be a problem for the X-Box 2.
Lord knows what Nintendo wanted with the Gamecube, but I'll tell you what it didn't want to: Fix the mistakes regarding 3rd party support that plaged the N64. Nintendo, for better or worse, plays the game by it's own rules, and they design their consoles for their own needs, not the needs of other developers. As much as they say they lowered licencing fees and made the Cube an easy machine to develop for they still ignored everything the PS2 had (And like it or not the PS2 is the standard of this generation) and created the least viable plataform to develop for in this generation. Most people buy Nintendo consoles to play Nintendo games, but instead of changing that (And build *the* console to own) they're contend with it, therefore right now Nintendo makes great "secondary systems" as most Cube owners have a PS2 or a X-Box as their main system. And right now I'd say that of the big 3 Nintendo has the worst image with the public and with developers, regardless of how well the Cube performed, and that doesn't bode well for it's future.
Of course, as long as there are people like me (And like most of you, I bet) Nintendo will sell consoles but right now I'd say that Microsoft has a bigger chance of dethroning (Bet I wrote that wrong) Sony than Nintendo. Not that I think Sony can be removed from the top anymore...
Oh yeah, and on topic: That's good to hear and I hope Nintendo delivers on those expectations, otherwise their stocks may plummet again after this year's E3.