Uh, why should they find or do something drastic? They just have to continue supporting gamecube to the end, and not drop everything or delay every announced titles for 2005 for N revolution. Dropping N64 kinda hurt GC's initial image with gamers, and probably still does with some. Why do you think PS2 sold so well initially? Because it promised to do what playstation did, gamers had a good opinion of the system and were still getting kickass games on it when the ps2 hype was starting up, they were satisfied.
It doesnt garantee success for their next platform, but it certainly helps to satisfy your existing userbase and fans, as they'll likely be looking forward to their next platform if they saw gamecube as a good gaming platform.
RE4, Zelda, Fire emblem, Advance wars, Geist, Virtua quest, Viewtifull joe 2, Killer7, donkey kong jungle beat, phantasy star universe, odama, Animal crossing 2 (?).
A lot that im looking forward to and these are mostly games that were announced in 2004 and got delayed or will be released in japan this year but not in the US till next, so im pretty sure there's still games waiting to be announced for next year.
With these, i can definitely say that i'll be a hell of a lot more happy with my gamecube purchase than i ever was with N64, heck, i sold my n64 not too long after perfect dark's release, i was solely playing on psx. Its also one of the few reasons why i bought gamecube so late, as much as anyone like to point fingers at me for being a nintendo "fanboy", i bought gamecube a full year after PS2 (which i bought during GT3 pack), and half a year after Xbox, another reason is the initial launch didnt impress me and i was in waiting mode to see where it was going.
Seriously, why should nintendo turn things around for gamecube? Gaming wise, im already happy with the lineup they've churned out, and im still looking forward to a lot more gaming in fall and 2005, they got some important 3rd parties onboard and it pretty much saved GC's face, there's still much to do, but i still think that capcom, especially getting massive support from Shinji Mikami was a tour de force. 2 RPGs from Namco, rpgs that bitchslap anything n64 ever had. Getting square to make games on their platforms, ok, not much has happened yet but im still hoping that the relations will go further. Square praising DS and not supporting PSP is a good sign so far for nintendo. And they're making profits, tons of it, they're even the #2 publisher in the world, only after EA.
For gamecube its too late, keep supporting the platform and make your userbase happy and anticipate their next platform is the only thing they can do, for revolution they obviously have some ideas, will it be good or not, its something we'll know next year.