Traditionally, you'll need to have at least 1 published game done, have a proper office as a main base of operations - like a physical office, not an office in your house. Also, you'll need to be incorporated - easy task, costs about $400 US. Then Nintendo visits your office, makes sure you're legit. THen you fork over money for the dev kit.
Now, Wiiware is aimed at smaller devs, and might have less demands, not sure exactly on that. Havent researched it yet







