Well my Uncle sent me a link to this website saying the following about the Madden '10 cover:
"Some interesting finds out there on that thing called the inter-web regarding the possible cover athlete for Madden NFL '10. A shadowed out version of the upcoming cover of the game has leaked and it bears a strong similarity to an iconic shot of Peyton Manning. Decide for yourself, let us know what you think."
Here is the link to the site that has the shadowed out cover and the "iconic" picture of Manning:
http://my.thescore.com/branded/archi.../19/12428.aspx
There is also a screenshot of Manning in Madden '10 that Manning looks weird in to me.