back in the days of domaingrabbing, this was quite a lucrative thing to do.
register a domain that you think will probably be useful to some big corporation some day.
like iphone.com
or eink.com
back then people could charge a lot of money to hand over the domain.
now, with all kinds of laws in effect, this is hard to do. i guess amazon decided that kindletalk.com is a good thing to have so they probably paid the owner the 9 dollar registration fee for a year and asked him to hand it over to amazon.
unless his name is one Mr. Kindle Talk ....