Collapsing discussions
Collapsing a long discussion (e.g., by clicking Acknowledge) will no longer scroll you to some seemingly random spot on the page. If the top of the discussion is off-screen, Reviewable will automatically counter-scroll the window so it'll look like the discussion is collapsing from the top down and remain within the viewport.
BTW, the rewrite is making good progress! The end isn't quite in sight yet but it's just over the horizon. :)