I have a site that has been indexed for a few years. Today I noticed that google also has indexed the SSL version of the site. The http and https versions contain the same content. My question is, would this be getting me a penalty? If so, how to I stop google from indexing the https? I guess I can have a noindex meta if the script is using SSL, is that the best way? If I am being penalized, will simply getting it un-indexed remove the penalty? I guess thats all I have for now. Thanks for all the great information!
I don't think you will get penalized for 2 pages on the same site having the same content. On the other hand, your PageRank will be spread over these 2 pages, so having only one indexed is better. Try to find out if there is a link to this 'https' page and if so, consider changing that link.
With a noindex meta, Google will eventually drop that page. If you want to speed up that process, go to the Remove Content from Google's Index [google.com] page after you added the noindex meta.