I think this will be great for the Map Gallery. I have set up a private CartoTalk account so your documents will not be accessible outside of Cartotalk. As long as your PDF is on the web somewhere you can embed it in a post by using the PDF tag. Eventually I will add a way to embed Scribd documents that you may have already uploaded.
By using the PDF tag there is no limit (other than upload times) to the size of a document you can post.
[pdf]Url to a PDF[/pdf]
Here is an example of a file I uploaded.