For Mac users still on ppc this is damn near essential!

Flash player on YouTube takes up all my cpu and constantly skips frames. As a temporary fix I got a QuickTime player bookmarklet to play some of the HQ videos with Quicktime which worked pretty well except not all videos were available like this, and of course, having to click it every sodding time was a pain.

Now I can just browse within this app (much quicker than doing it through YouTube) and get a decent quality mp4, all for keeps!

Only thing I would say is that after switching to grid view the buttons disappear, but still work. Bizarre. Just one bug, it can slide :)