Look at the Facts:
-Banjo and Kazooie would represent one of nintendo's greatest second party devolopers who helped the N64 be a suceess and arguably their best console to date (IMO anyway).
-Probably the 2nd and 3rd greatest platform games on the n64 were Banjo and Kazooie and Banjo-Tooie. (After Mario 64 of course).
-Very popular with everyone. Its just no one belives they have a chance.
-Great moveset potential.
-OWNED BY MICROSOFT.
Lets look into that. Why would microsoft stop nintendo from using Banjo and Kazooie? Well,
why exactly? Banjo and Kazooie would not exactly raise Smash Brothers sales highter than they are (Solid Snake and the inevitale Sonic inclusion will do that) and Microsoft dont have a game to compete with Smash. Banjo and Kazooie 3 is coming out exclusivly for XBox 360 next year. What better way to advertise and plug the game than on the nintendo Wii and on what will inevitably be its biggest selling game (or maybe Mario Galaxy will clinch it)....exactly the console of choise for the platformer audience. B+K's inclusion in Brawl would greatly increase Banjo and Kazooie's sales and might even sway some Nintendo fans to buy a 360...im sure many are considering it.
And in a way thats why they wont be in. Because
nintendo wouldnt want to help
microsoft in any way and not the other way around. BUT it would seem they have no problem plugging the PS3 exclusive MGS4, even including music from the game. So its not impossible as many would argue. And the only thing stopping them from getting in is Nintendo not Microsoft.
Oh and the fact there are more important/popular third party choices.
cheer up boys...your hopes of getting in Smash are far from lost