Well, it will be soon anyway. One of the features that I love about the Nintendo DSi is the fun photo editor, and in the next Nintendo DSi update coming this Fall, you'll be able to send those hilarious custom photos directly from your DSi's photo library to Facebook. And as we all know, eventually, everything ends up on Facebook.
Japan and the UK will enjoy this feature first, but it will be a cinch to install for everyone. Just go to the DSi Ware section, download the free update and the Facebook app, and you're all set to go to upload your DSi photos to your online album.