They've only sent out a couple to reviewers according to Jody at BFL.

There is no official count on the number of PAID orders.  That said, many orders likely have multiple units purchased, so it's impossible to say.  If I were to guess, I'd say around 20,000 units.  Which is about as good as anyone else's guess.

One thing to keep in mind, especially with the Jalapeno's is that many owners will quickly resell their units on the used market after a short time when they realize that it's not a money printing machine, and to recoup their investment from people who are eager to join in the ASIC "Gold Rush" and aren't aware that they'll make $1 a day as the difficulty skyrockets.  Before too long, since these items are not multipurpose like a graphic card, you will find these selling for pennies on the dollar because they'll be effectively useless.