Recently I signed up for Libox and started to play around with it. For it to be in Alpha; it's not too shabby.
I tried out video streaming and video streaming I wouldn't recommend unless your on a 64 Bit computer with 4GB or more. Video playback is rubbish if anything and is ultimately an annoyance for more users than an added bonus.
Photo viewing is nice and works like a charm, you can also view documents within their web interface pretty well also.
Overall, it's an okay place to store your media but until video playback improves greatly; I won't be relying on it.