Here are some new Gmail keyboard shortcuts:
d – open a compose window in a new tab (Shift+c opens it in a new window)
, – moves the cursor to the first button in your Gmail toolbar
{ – archives the current conversation and moves to the older one
} – archives the current conversation and moves to the next one.
There are some subtle differences between [ (“Removes the current view’s label from your conversation and moves to the older one“) and { (“Archives the current conversation and moves to the older one“) or between ] and }. Their effect is identical when you read conversations from your inbox. If you open a conversation from any other label, [ will remove that label from the conversation, while { will remove the conversation from the inbox.
The Gmail shortcuts page has been recently changed and these are the new shortcuts I’ve noticed.