Before I switched to Ubuntu I used the media management program WhereIsIt to inventory my CDs and DVDs, even the harddrives of one of my computers. Since the discs are still around (somewhere) I would like to find an online substitution for WhereIsIt. I already found the list of Ubuntu programs for media management (DE) and read this similar question. Though, I think a web based solution makes much more sense.
What do you recommend? Please add a short feature description (supported formats, import capabilities) with pros and cons.