with all the tumblr talk here is my
tumblr is a great way to generate buzz, links and traffic to your sites. but dont waste your time with tumblr subdomains, use your OWN domains and back up your posts regularly. this way when tumblr shuts down your sites (and eventually they will) you can quickly slap up a wp blog, import the posts and still leverage the traffic and your hard work.
ok start hating