Mine arrived today too. The metal shield was a bit bent and mishapen. I was able to get it rectangular again, and fit it to a USB hub on my PC.
The chipset is indeed BCM20702A0, as wallyhts pointed out up top. This is apparently a fairly standard USB chipset used by Lenovo, Dell, HP, and others. Windows drivers are easy to find for it.
The next big question is whether or not a 3rd party dongle with this chipset will work? Of course, it will depend on the final selling price from Dish, and the price of the generic dongles, that will decide whether it worth one's while to bother with a generic.