I decided to pre-order a DS Lite. The timing is great at GameStop. We're doing a deal where you get $20 extra trade-in credit when you trade in any system, so instead of getting $50 store credit for my old DS, I'll get $70. On top of that, I have 4 DS games I'm going to trade in, and I'll get an extra $10 for trading in 4 DS games. So my DS Lite is almost already paid off.
I just figure getting the DS Lite is a no brainer now, since almost every game I have pre-ordered is a DS game. There's just so much coming out for the DS now it's crazy.