Not really sure what you mean with wireless SD cards...
Anyway, what I'm more concerned about, really, is homebrew.
At the moment, the homebrew SCENE is interesting, but the catalogue of finished homebrew games that are fun to play isn't very extensive. But hey, the machine hasn't really been "out" for very long, and it seems like a lot of people are catching on to it. If one person can spread interest to TWO people and so on, we'll have a big, nice community by the end of the year. I think that in time, it could even happen that several forums regarding the GP2X will appear. Personally, this board is already getting a bit big for someone like me, but I keep to a few specific sub-forums, so I'm okay.
If you look at the Talent Thread (linked in my sig) you can see a lot of people already working on some interesting stuff, and I think that within the next six months or so, we'll start to see the fruits of their labours. Once we have a good heap of great, polished homebrew titles for the Gippex, I think that a great deal of potential buyers that wouldn't buy it NOW will be more likely to get the machine, and then they will trigger THEIR friends, etc etc.
I also see a few commercial games being released, something I'm also looking forward to. Thing about freeware is that it'll always seems sort of "out there" for the teeming throngs of normal people. Some commercial titles with a professional-looking website for purchasing said titles is all-important if we want to get as many people playing this thing as possible. I also think that a website somewhat like the file archive but less unwieldy and big (imagine yourself being the average Joe looking for games for this neat new GPwhatsit) for the new people.
Those are just my two farthings.