Perhaps it's just a chance of the initial poll. We'll see in the next days.
However, it may be a good association of lightweight products. MySQL is a small, ubiquitous database server, compared to other more heavy products that need to be distributed in DVD, and the Vi family (with my favorite vim) is also small and ubiquitous.
What I loved a lot while working as a consultant is the ability of using syntax highlighting even in the most basic environments (i.e. a ssh connection on a terminal emulator) and the availability of vim in every operating system.
What's your take? Cast a vote for your favorite development environment.