TheOptimizationIdiot - 12:38 am on Apr 1, 2013 (gmt 0)
So, then the answer is yes and no?
I think you'll have to define indexed to get a more direct answer to your question.
If you mean "indexed" as in you search for some unique string in it like @#GDGRINROIBGQREIQ$#@%$# and it'll rank in the results for that query without the actual string on the page, then no not last I checked or heard anyway.
If you mean "indexed" as in they know it's there, have a copy of it, and use it on occasion (sometimes more often than others) then yes. There's info all over about it:
The description attribute within the <meta> tag is a good way to provide a concise, human-readable summary of each page’s content. Google will sometimes use the meta description of a page in search results snippets, if we think it gives users a more accurate description than would be possible purely from the on-page content. Accurate meta descriptions can help improve your clickthrough; here are some guidelines for properly using the meta description.
I'm sure you'll find plenty more by searching for something like "google page title and meta description use" in your favorite search engine, or something like "matt cutts youtube meta description" might turn up more info.