Please have a look a this site: http://www.baccaratgirls.com It is pretty popular in terms of backlinks, but ranks poorly for its link popularity. The text on the site is pretty dark. It is known that Google penalize if a webmaster wants to hide text from the user but leave it accessible for the SE crawler. Do you think this page could trigger Google suspicion and poor ranking as a result?
Text color looks fine. I have noticed that the text on the page is used elsewhere on the net as well. Google may see this as duplicate content.
unless you want to hide text and hide it on a page, google will not penalize you...maybe a different color would be better for your traffic though....
I think the text color should be fine. Since that is an oudated black hat technique, I'd be surprised if Google penalized just for using a text color that is close to the background color.