Why does AT&T launch a phone (and send review units) and attach 4G to it without having their network ready? All three of the other carriers managed to launch 4G devices and have a significant 4G footprint in place to at least show speeds off for reviews.
Secondly, its not as if magically, come March 1st, all the backhaul will be in place to deliver "4G"/6Mbps+ speeds to most of its customers. There will probably be a substantial amount of customers who buy the Inspire 4G who will not see "4G" for quite some time. They should know what to expect, hence the notes the reviewers have made.
I sound like a broken record