Amazon has gone on a hiring spree to bolster its Kindle line-up, presumably in anticipation of a rumble with iPad (also, diversifying its software). Not noted here is the hidden listing for “5 burly men with axe-handles, masks, and purchasable sense of discretion”….

After the iPad announcement, I debated with my colleague Brad Stone whether the iPad would kill the Kindle. I argued that the Kindle could never compete with the iPad’s user interface or hardware design. Brad said that the Kindle was here to stay, that it was a device “for book lovers, and the iPad is not.”

Then, a few days later, we reported that Amazon had purchased Touchco, a start-up based in New York that specialized in a new touch-screen technology, which signaled that the company was going to stay the course with the Kindle.

But the ferment of activity in the job listings gives some hint about Amazon’s plans.

For example, the job listing for a “Software Quality Assurance Engineer” suggests that some kind of project is moving from concept into a development phase, where this kind of engineer helps guide the process through to final production.