This is a win-win as far as I'm concerned. The early adopters are the ones who would be most likely to buy downloadable games anyway so I think it's quite the gesture. The game line up for the coming year is incredible and a price drop of this magnitude will definately increase sales which will just get more games released.
My wishlist for the other GBA games:
Either F-Zero
Either Advance Wars
Mario & Luigi
Either Zelda
Super Mario World - the best Mario game
Man, the GBA is like the pinnacle of what I want out of a handheld. Such an amazing library.