To be honest, I could hardly see a difference - perhaps that is a problem with the display of videos on my machine ...
Or it could be a problem with Windows 8 in general: while the media center on w7 can show my library without problems, the media center on W8 crashes and restarts ... same program, different OS, though.
Well, I have windows 7 before this, but the same problem persists.
You could try full screen when seeing the YouTube video. and also HD would help too.
You would notice that the "blue box" doesn't follow the mouse in time. it "lags".
Or you could try yourself, 30+ song with moderate long Japanese tags[title,filename,album,etc.](show it in the column) and try to select it.
The lag will be noticeable.