I posted a screencast on Heroku a few months ago. Since then, my company has moved all of their stuff to Heroku. It has been working really great for us.
I've had my blog on GitHub pages for awhile. I recently came across a good article on running Jekyll from the Ruby5 podcast. It was really easy to get setup. So far, I'm a fan of my new setup.
I'm still working on my Rails 3 version of my blog when I have time. Lately, I've been playing a lot of music and occasionally dabbling with Markdownr.com due to a recent spike in traffic (thanks to @defunkt).