The DSi XL does not rule out a DS2. The former is a very minor enhancement, it's closer to a PS2->slim than a DS->DSi change. It's to help the DS reach further, and the announcement of a DS2 (which probably won't have the giant screens) wouldn't impact much on DS1 XL.
A game I'm developing with some friends:
www.xnagg.com/zombieasteroids/publish.htm
It is largely a technical exercise but feedback is appreciated.