I'm using Version: 0.6.9 (SVN r3447) w/ Qt 4.6.3 (compiled with Qt 4.6.3) and MPlayer SVN r31918 on KDE 4.5.3 Debian testing. When SMPlayer plays ogv files, half of the video is upside down or flickering with some bits jumbled up and out of order, and the timeline jumps around from zero to something else like where it's supposed to be. Dragon Player Version 2 plays the same files fine. SMPlayer quit playing the file in the picture before a minute passed.
SMPlayer playing The Normals ogv, and timeline hasn't left zero. Dragon Player plays it fine.