The Gmail keyboard shortcuts are generally excellent. One of them (⌘-Shift-7 to start an ordered list) seems to work for me for a while after restarting Chrome… then stops working. I note that the others keep working (so ⌘-Shift-8 to start an unordered list and ⌘-Shift-9 to start a block quote always work).
And ideas on how to track down why this might be happening?