I ran to get on the clipper after the O2 2010 show, with the hope of it beating the train back to waterloo and be able to catch the last train. It stood stationary for ages and eventually got to waterloo when the station was closed. Avoid. Getting it TO the venue is great though, lots of GNR fans having a booze up on the way.
Same here in 2010. I pre-booked the clipper back from the show so got on that quickly but as you say Waterloo was closed and ended up getting a ?120 taxi home! This is why I've booked the Holiday Inn in Greenwich
Chilly - is your hotel walkable from the O2? Thought looking at the map there's no bridges nearby! If the tubes are running then I guess try and get the tube from Greenwich. Otherwise maybe just book a taxi. The clipper is great but it will only stop at London Bridge and then Waterloo which is no help for Docklands.