I'm expecting a Wii successor in Spring 11, so I don't think Nintendo is planning a revision.
If however Nintendo wants to hold off on a successor for a while I think we will see a redesign at E3 next year. I agree with what dunno001 was saying. I think the logical thing for Nintendo to do would be put in a hard drive/or a much large flash memory. Nintendo seems to legitimately want to improve their online store/functionality. The 3DS channel is looking much more streamlined that the DSi/Wii, and maybe a Wii revision could take advantage of a similar strategy. I think with the harddrive maybe they could expand WiiWare's size limitations from 40mb to double or triple that. I think I read that Black Ops Wii and Conduit 2 supports patching, the extra storage space could help make patching more available for more games. Also more downloadable content like map packs for FPSs would be an option. I think this strategy would be most relevant in that it would just be another step to strengthen 3rd party relationships. I think just a change to the physical appearance of the console, and a new marketing campaign like Sony and Microsoft did with their revisions, and that should give the console a bump in sales for awhile.
I also think the red Wii bundle will help quite a bit this holiday, and Iwata said in the financial report that new bundles would be an important strategy going forward, so I expect to see a few more instances of that type of thing.
