lucy24 - 7:32 pm on Apr 23, 2013 (gmt 0)
Treat it the same way as "crawl errors". If you look and your reaction is "Yes, yes, what's your point?" then ignore it. But if you look and say "Whoops!" then the robot has given you information. Last time I personally got a "duplicate meta" notice it was a page I'd created by copying an existing page and changing all its content. Forgot to change the meta description, so there you are. Thank you, robot, wouldn't have noticed that.
Now, if only they'd stop ragging about short metas. Look, search engine, sometimes "about widgets" is all the human user needs to know.