Just deciding which to use. Movable Type or Wordpress. MT has one important strength: static publishing. Since wp has WP Super Cache, is there any reason to use Movable Type?
You're not telling enough about your needs to tell which one might fit them better. However the MT publishing model and WP super cache are not really comparable. The former offers you out of the box a variety of publishing models (static, dynamic, batch queue) AND various cache mechanisms which you can mix depending on the content, while WP Super Cache is a plugin that is here to alleviate the performance problems inherent to the always-dynamic nature of WP.
Let say you're serving HTML pages, say with bits of PHP in them to make the comparison even closer (publishing static HTML isn't WP's strength at all), here how the two systems compare:
Movable Type in static publishing mode: - add/change content -> MT will publish only those files that need to be rebuilt, on the filesystem. The database is solicited only at this point AND only for the templates that were not already pre-calculated and cached. - visitor requests a resource (HTML, XML, PHP, whatever) -> web server fetches the file (possibly interpreting it through PHP, server-side includes etc.) and serves it. MT and the database do not get in the way here.
WP + Super Cache: - add/change content -> WP updates the database - visitor requests a page (a PHP script) -> web server launches WP through PHP, WP pulls content either out of the database (then cache it) or out of the cache (which requires additional CPU and memory), sends it back to the web server which sends it back to the client. Way more layers and resources involved here at every request.
The key strengths of MT WRT to WP are that:
If I may rephrase the question (it can also help answer yours), is there any reason to use WP? (There are, but I don't know your actual needs ;-)