This instructable shows you how to upload your Flickr photos straight to your Facebook Photo Album.
There are several Facebook applications that let you import your Flickr photostream to Facebook, but photos appear in a separate box on your Profile. None of these apps lets you upload photos directly to Facebook photo album, so you could tag them in a way Facebook understands, mark your friend on them etc.
This method uses the unofficial Flickr2Facebook uploader by Keebler. To use it you will need:
-Greasemonkey addon for Facebook