The following are the official keyboard shortcuts for Google Plus as of 7/8/11. I will add more as they come in. If you find any please post them in the comments. (Excerpted from the mother of all Google+ Tips Guides)
j: Click ājā to navigate down to the next item in your stream
k: Navigate up to the previous item in your stream
@ or +: mention someone in a post (Guess Twitter didn’t patent the @)
q: While on the Home tab, press qq to move your cursor to the search for people to chat with box.
Space Bar: Scroll down stream
Shift + Space Bar: Scroll up stream.
Enter: Hitting Enter when focused on a Post opens up the comment box.
Tab + Enter: End comment.
Unofficial Shortcuts:
Ctrl – (minus) (a/k/a Zoom Out) on the Circles page makes Circle management much easier. On the Mac it’s pinch to zoom.
Tab: Scrolls through links on a page (this is a Chrome shortcut)

4 responses so far ↓
1 Prismic-Reflections
Thanks for this useful info, it will help to save time
2 Kim
‘@’ has been used for pointing a comment ‘at’ someone long before Twitter
3 Amy
They’ve just added ‘m’ for mute as well.
4 tuhin
we see google+ votes is one of the top social stuff but here is also many site like that gplusvotes.com now its time to see their activities and how much they will satisfy us with their performance. will come here to see your reply, thanks.
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