Be aware that you can no longer play gameboy advance games with it (not that it matters--I never do with my lite).
And no there are no exclusive games per say--besides the downloadable games--which is why I haven't and will not buy one yet.
If you don't have a Lite, then I think it's worth it to get the DSi, but if you have a prefectly good Lite, there's no way I would buy one yet.
BTW it's been out in Japan for over 6 months with no exclusive games...