I know what you think: "Wow, Marc sure is one lean mean blog-switching machine!";.
And you're right :D Mephisto was a pretty decent blogging engine, but ever since 12-18 months ago, the development is a bit slagging. XML-RPC doesn't work in the current stable, inserting Images from the "Bucket"; doesn't work, the wiki is down and nobody seems to care/do anything, …
I also don't use disqus anymore. Disqus is pretty nice, but I want "email me when new stuff shows up"; + openID
To convert the posts and comments from Mephisto, I used the python script that can be found over here