The autorefresh of the Code Review Board has some disadvantages while you are working on the list of files or on the list of review items:
* Your position in the scrolling list is lost.
* The review items are reordered according to their Open/Closed status.

It would be better to just signal a refresh is due by coloring and or flashing the Refresh button (e.g. green or orange). The user can than choose if he wants to refresh the Code Review Board immediate or some time later.