If you've got a European, Australian or Japanese DSi, you can now go to the settings menu or the DSi Shop to be presented with a system update - Once you've done this, the photo album will get a new feature.
After taking a picture, there will be a new button when looking at it in your photo album. Marked with a white f in a blue square, it's quite obvious what this does - It lets you send your picture directly to Facebook, that is, if you've got a Facebook account! The first time you try this feature you'll be asked to enter your Facebook login e-mail and password, but after that you're free to upload as many pictures as you want.
Once you've uploaded a picture, a new photo album will be created on your Facebook account, titled "Photos from Nintendo DSi," which will have every picture you upload in the future. Simple and quick to use!
We assume this update was released in Europe/Australia today to coincide with tonight's Wii/DSi updates, so we don't expect North American DSis to get this update until Monday. But you never know!