http://www.amazon.com/gp/feature.htm...tag=gmgamzn-20
I'm overjoyed and am yodeling and fondling myself with jubilation at the news the plugin works with older Kindles (definitely the Kindle Keyboard and possibly the two earlier iterations), but I'll believe in the Mac version when Amazon actually releases it. Still, they ought to have included Linux.
Of course, this would be a lot more exciting (which is to say exciting) if (1) pdfs on a pearl-screened Kindle were practical and (2) it was previously impossible to save our docs as pdfs.