The wii has a rapidly growing install base. Devolopers will make games for it, and it will last as a console. 360 went through a horrible drought of games after launch, and then bam, FN3, Oblivion, GRAW, Battlefield 2, etc were all released in the spring, followed by a good summer, and what has been an excellent fall.
The ps3 and Wii will follow a similar pattern. Theres already some system selling titles on the horizon for both, and more and more games will be announced. Theyve been out a month now guys, give it time!