I came across this very informative summary of the current (purported) rights that various on-line communities claim over the content you, the user, uploads. For example, Facebook’s terms of service are completely horrendous, whereas Flickr is relatively respectful…
You may have read about how Apple, in its benevolence, is finally releasing its entire music catalogue in a digital rights management-free format – i.e., you can copy them freely as you see fit. Sounds great…