I got no video when playing, neither in clip nor project monitor. Audio is heard and I got video when scrubbing but as soon as I hit play there is no video playing, only audio and an empty clip/project monitor.
Tried all video codec settings but none gave video playback.
Tried a lot of different video-files with different codecs and containers but with an equally dissapointing result.

Just installed 0.7.6 from PPA. - Had video playback in previously installed 0.7.3.
Ubuntu Studio 8.10, 64-bit, dual core and 4Gb RAM.