As I have argued before, Donkey Kong is a part of the Extended Marioverse. The DK series is a spin-off of the traditional Marioverse and as such deserves a place in the wiki, but only of secondary importance, as it is seperated by one "degree". The majority of our work should go towards completeing the traditional Marioverse (i.e. games where Mario is the star). Other spin-off series include the Wario and Yoshi series. A lot of enemies and species in those series don't appear in the traditional Mario games, but we consider those spin-off franchises a part of the Marioverse nonetheless. They are spin-offs just like the DK series and thus classify as of secondary importance (again, one degree of seperation). However, the DK series has also spun into the Banjo and Conker series under Rare's direction. Again, a spin-off is a part of the same universe where it came from. In this case, Conker and Banjo are a part of the DKverse. However, the DKverse is part of the greater Marioverse. As such, Banjo and Conker are a part of a very extended Marioverse. However, since they are the spin-offs of a spin-off, they are only of tertiary importance to the wiki (this time, two whole degrees of seperation instead of one). That means they don't have as much importance as traditional Mario games or the DK, Wario, and Yoshi sub-series. They are a part of the Marioverse, but not as important.
Super Smash Bros., on the other hand, is a crossover. That means it too is a part of the extended Marioverse, but only from the perspective of the Marioverse. That means while Princess Zelda is a part of the Marioverse, all that is "known" about her is her role in Super Smash Bros. Melee. Information from the Legend of Zelda franchise is not of any importance to the Marioverse. Only her Super Smash Bros. appearance is. See the
Princess_Zelda talk page for more information. Again, because the Super Smash Bros. series is one degree of seperation from the traditional Marioverse, it is of secondary importance to this wiki. The Legend of Zelda series is not a spin-off or a crossover of the Marioverse, and thus has absolutely no importance to this wiki. We could expand and start creating articles about the various items and places in the Super Smash Bros. series (including items and places from other series that appear in Super Smash Bros.). Of course, this would be of secondary importance.
I believe any information from the Banjo and Conker series as gained from the XBox is completely valid. Just because it isn't Nintendo, doesn't mean it's not valid. I mean, look at how many great Mario games are being developed by third-parties (such as the Mario & Luigi series).
Lastly, I think it would be foolish to include series that are independent of the Marioverse and can only be conneceted via the cross-over Super Smash Bros. Pokemon and the Legend of Zelda are independent of the Marioverse. They emerged from different sources and are in no way related to the Marioverse (i.e. they are no spin-offs, but their own independent franchise). They are unrelated and have no place in a wiki about Mario. I would also be deeply saddened to see this wiki transformed into a general video game wiki. I liked that the Super Mario Wiki focused on Mario. That allows us to get a lot more done. If this wiki was open to all Nintendo or all video game franchises, we would be bogged down in too much information. We could never get anything remotely complete. Plus, there are already two Nintendo Wikis out there, and many more video game wikis. The Super Mario Wiki is unique in that it is the only wiki out there that focuses on the Marioverse in all its forms.