Tis worth saying with regards to launch games - these were the launch titles for the original DS in the USA:
Based on this, I don't think it's unrealistic at all to potentially see a launch with a similarish set of basic, starter launch titles. The Market is a different shape now, of course, so there'd have to be a token puzzler/brain training style game in there too, but when you consider Nintendo has 2 N64 remakes confirmed for the machine already, those could be ready day one as the bulk of the games already exist, and I'm sure other publishers will have absolutely no problem churning out something rushed for a 2010 launch,