My money is on yes.
My best guess is the iPhone 5 will be a minor hardware update. It'll basically be the iPhone 4 with a better processor, maybe a better camera, and other minor tweaks. The iPhone 5 might be a CDMA/GSM phone so all carriers have one model. It will not have LTE.
This summer the focus will be on iOS 5.x, with a software overhaul in store, and the focus will not be hardware.
Then in the summer of 2012 we will see a new hardware refresh with LTE and other 4G capabilities.
I just don't see Apple doing a major hardware refresh considering the 4 was a pretty big change from the 3G/S. Think 3G -> 3GS