The guys at Gamecyte did some snooping about the security on the DSi, and they found some news that may upset those worried about secure connections.

But what of the new Nintendo DSi, which sports comparatively secure WPA encryption? Is there any reason for DSi users to buy the Nintendo router? Iwata answers this one himself: Though the new browser and those programs designed exclusively for the DSi will use a high level of security [e.g. WPA], existing DS software will use existing encryption.

It's not a deal breaker for me by any means...how about you? I honestly don't worry about that stuff too much...but perhaps I should.

Link