its been spotty service around towns for awhile now. the xda forum members have been in discussion for awhile now. check it out over there : 4G Minneapolis - xda-developers
I was up there this weekend and YES there is 4g. And it has been testing for a while now, but you are able to get a really good speed over by the General Mills Campus. Other locations I was not able to test. Connections and locations are still really spotty, but the hope is that the city will be up and running with full 4g soon!