this is only good thing the microphone is there for....
Not nececarily, it can be used for games like Seaman from the Dreamcast... theres tons of ways to use the Microphone not just talk to others
The WIFI and Wireless connectivity options are very interesting. I like the idea that you could detect others (How far?) with a sleep mode, start up possibly send them an IM asking them if they want to play, and play Mario Kart DS wirelessly with one cartrdige on the go... Thats just plain cool
the internet possiblities are interesting, cause if you connect to a WIFI Hot Spot, (one of the malls where i live has one) You could do the same thing but with people across the country. It will simply take companies to actually use this.... I dont know how many will