When I said the K2 wasn't listening on any TCP ports, I was somewhat mistaken.
PORT STATE SERVICE
2812/tcp open unknown
28082/tcp open unknown
40317/tcp open unknown
2812 is monit. And 192.168.15.200 isn't in the list of addresses authorized to connect. I can connect to port 40317 and spew at it all I want, but the Kindle doesn't acknowledge my input.
I only got it listening on 40317 after I...did some stuff I'm not going to talk about yet. That currently hands me an "ACCESS DENIED" upon connect.
I've also got the Kindle 2 accepting my hand-rolled firmware updates, not that I've managed anything useful with them yet. (Hint to interested parties: igorsk's tools are still useful on the Kindle 2, but unlike the K1, it actually cares about some of the metadata his header writer skips)