KavazovAngel: Is anyone into the beta? Can you tell how it is?
Arkose: It's a bit underwhelming really. It only supports a handful of games, and not even all of the mods for those games are on it. Once it's actually got all the games and mods supported it should be a pretty good way of easily installing these things. For the moment, however, you're better off doing it yourself.
As for the number of mods, they say on the page linked by OP that they want to mainly host finished mods or mode being worked on frequently(no dead projects) of good or better quality...making it easier to find the pick of the litter, as it were, and to download and install them quickly instead of searching through lists of mods(alot of them dead or not worked on in quite awhile and/or utter shite) on ModDb.