How many units sold total? Only a rough number!
roughly few thousands
I had hoped many more would have been sold by now given 141,614 subscribers to /r/Bitcoin and 393,788 accounts in bitcointalk. Plus the hundreds of millions spent on ASIC preorders.
Currently there's no support for the Trezor in the wallets that people are used to using, thought that'll change eventually.
I wasn't in a huge rush to order a Trezor for myself because I'm reasonably able to secure my coins, and didn't feel that they were at risk. The main reason that I picked one up was more so that I could evaluate it and decide whether to start giving them as gifts to friends and family that use Bitcoin.
Speaking of, any plans for a Black Friday discount?