I just acquired the Harmony 720 (my first) and so far I like it. One significant problem: for some reason, the update process doesn't work right. It generally goes very slowly, and will stick at 80% (verifying step). I've learned I can cancel the process at this point, detach the remote from the USB, remove the battery for about 20 seconds, then reinsert and I'm good to go...but I'd prefer if the update worked right. I haven't seen any other 720 posts out here, but any help would be appreciated...

i've had a similar problem with mine except that it will not even start the update process. it shows "gathering information..." prompt as if it's going to begin and then sits idle. I tried letting it sit at first to see if it would begin and it ended up timing out overnight.
I too found that I can simply cancel the update, unplug the usb, and then immediately reattach the cable. I then works fine.
It doesn't bother me enough to call tech support. I chalked it up to another quirk in their software. If you have your USB attached to a powered hub, you might try attaching the cable directly to your computer's usb out to see if that helps the situation.

Got on the phone with one of the better Tier 2 tech support guys. He had me delete the Logitech folder from Documents and Settings, and this cleared up the update problem. It now updates in a few minutes like it should.