Actually that is an important point - facebook is not the best place for a photographer, the terms and conditions of the site have some nasty wording in them that means they (facebook) can commercially use your images without your say so. They claim that this is something that they do not and will not do however it would not be in their TC if it was not something they had in mind.
Flickr is far far safter and better in terms of its terms and conditions as well as in its overall layout and features. Image quality should be about the same however many people do not sharpen images after resizing for the internet (or they let the uploading site do the resizing automatically). However only flickr does resizing images well (infact it does it very well) most of the others will soften the images as they resize.