No specific info about version 1.6. Please visit the main page of tumblr on Mac Informer.
MarsEdit is an easy way for editing, viewing and updating blogs.
This tool can create a copy of your blog’s content viewed on any computer.
Cute Tumblr client for Mac OS X and the sexiest way to blog without browser.
This application keeps all your Tumblr posts archived locally.
myTextPost -The text publishing tool for serious tumbloggers.