There's a brief bit of M.U.L.E. News on the Ozark Softscape Legacy Website, which is operated by the children of Danielle Bunten Berry (nee Daniel Paul Bunten), the late designer of the original M.U.L.E. (thanks Troll in the Corner and Mike Martinez). The update indicates a revival of the seminal strategy game may be coming:

We have opened the vault to our dad's extensive gaming portfolio and have been approached about making some of dad's old games relevant in todays gaming world with updated graphics and playability. It looks like M.U.L.E. is going to be the first one out of the gate. We're hoping for a revamped internet version late this summer.

Update: Apparently this was noted some time ago, but not here. Thanks Rhialto.