yeah, as soon as the switch from 21738 to 21882 was made, the UI would hang and not come up... I can see the network traffic running as per normal via a packet sniffer, and can see the disk access going on, but the UI just doesn't come up... I even tried rolling back and deselecting all of the tray UI effects then redoing the update, and restarting the computer, but to no avail.... so I guess I'm staying rolled back until the next iteration...