BTW, I should mention, I've gotten the same "they're just waiting to turn it on" story too! I use the store on Fruitville and Honore and also the one you were talking about: the one next door to Buffalo Wild Wings. The former is the one that told me last August that 4G would be on by December and I believe it's the same one as you (the one near Jason's Deli and Buffalo Wild Wings) that claimed everything had already been upgraded and was ready to be turned on. They told me that when I went in to cancel my contract to go with another carrier: stupid me I believed them and renewed for another 2 years. When questioned about the horrible Sprint cell signal in this area, both of those stores will tell you "your signal will be bad for another month or so: they are upgrading the towers". As far as I can tell by the info on this site, they haven't touched a single tower in this area... at least as far as 4G is concerned.
Mike