I guess support does not depend on the controller but more on the actual hardware and the user base. The first year is important - if the userbase is too small even the best controller can 't change the lack of third party support. Nintendo now needs to continue its strategy with innovation but also try to help developers and offer them good deals.
Square Enix did not leave the Nintendo because the N64 was a bad console - they hated cartridges and the price of them (including the little storage they offered).
Okay it seems many big developers are excited about the Revolution now Nintendo should use this and offer SDKs to implement the controller in an easy way, accept every good game even if it does not directly fit into their philosophy and most important try to sell your ideas!