I just set up a new blog using Pelican. My considerations were much like what you've listed. The price point seems right as well. I'm tempted to sign on, but my workflow is holding me back. I've got my Pelican based blog set up so I never have to leave Vim to write/organize/publish. Every other workflow I've tried for blogging has quickly decreased my output to... nil.

It seems to me if I switched to Silvrback I'd have to either use the admin interface to write (I assume it doesn't have Vim keybindings) or copy and paste from Vim.