The biggest problem is the voting arrows, which are far too easy to hit accidentally, and up/down votes cannot be changed.
Allowing changing of votes for a brief time (1-5 minutes) would be useful.
Improving display contrast -- setting a darker border and lighter main body area, would be vastly appreciated. Contrast isn't too bad, but can suffer under adverse lighting conditions.
A mobile-specific presentation would avoid resizing / sideways scrolling.
> Please provide a quoting markup. Existing workarounds of either prefixing with a greater-than sign
Or indenting text to present a
* Bullets would also be useful
# As would numbers.
And proper line breaking.
A collapsed view of comments (available through a Chrome plug-in) is another nice-to-have.