I'm having issues with V9 on playback. Not smooth using same media that works in V8. One workaround is to use selective prerender more. I'm using it on to cover simple dissolves and transitions on some MP4 video and to cover jerky pan crop movement on 3000 x 2000 JPEGs. It takes a few seconds but it works to smooth out playback. Renders are fine but its annoying to watch playback jumping and jerking. I realize there are deeper issues. V9, if anything, should work with a wider variety of media formats -- not less ! ..

This is not going to cover all the sins of V9 but for those unfamiliar with selective prerender -- it's worthwhile here.