Or you could just use your already owned DS and not buy anything.
As much as it looks cool to have those functions that are going to be added on, it's not a necessary buy. It's just branching out to another segment of the market. Nintendo is a business first. Right now the saturation rate of the Nintendo DS in Japan are at a high level, so high, that they can't possibly sell any more DS's to keep up with Sony. So the solution, a new DS. This is mostly a Japanese economic move if you think about it. Which is even more evident in why they're waiting till late 2009 to release it here. Sales of the DS lite in the US are very strong and the saturation rate much lower, all the more reason to put it on hold.
So again, if you want a DS with a camera, media functions, downloadable games, then sure get it. But if not, you're regular DS lite will just be fine.
I think one of the coolest game announcement of the conferences would be "Punch Out." Not a Virtual Console release, but an actual remake of the classic game. http://www.gametrailers.com/player/40745.html