Great News!!!!!! I discovered on another forum a link to an FCC website in which AT&T has filed applications for several tower upgrades in northern Michigan which were approved this past march, 2012. Searching further within this site it contains a proposed coverage map from engineering and a detailed dispcription of the equipment which includes Powerwave dual band broadband antennas. The coverage area is pretty much in the entire northeast part of the state including: Rogers City, Alpena, Mio, Fairview, Grayling, Gaylord, Cheboygan, Posen, Curran, Luzerne, and many more. It looks like this is the smoking gun which confirms AT&T's plans to rollout 3G/HSPA+ in northern Michigan
Here is the link: http://wireless2.fcc.gov/UlsApp/ApplicationSearch/