Well, I have just got to put my two cents in. I was inclined to go with single spacing because that is what printers and typesetters use. However, upon further investigation you are all right, according to the Modern Language Association. That should make you all happy. You can either double space or single space it's your call. However I agree, Murhagh, there is entirely too much nick picking on the forum. It takes away from the main objective and that is to help people play their Sims game not to teach them grammar. This whole thread was a waste except for a couple of constructive post.
Here's the link
http://www.mla.org/style_faq3, but the meat of the matter is stated below:
Because it is increasingly common for papers and manuscripts to be prepared with a single space after all punctuation marks, this spacing is shown in the examples in the MLA Handbook and the MLA Style Manual. As a practical matter, however, there is nothing wrong with using two spaces after concluding punctuation marks unless an instructor or editor requests that you do otherwise.
So you can be practical or go with the flow.
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