<p>I see parallels between MEF and Lua.  Both allow you to register methods and deploy as you need.  Are both MEF and Lua forms of IoC / Dependency Injection? </p>

MEF has nothing to do with Lua, and is nothing like Lua.
MEF is a framework for extending (basically, an awesome plugin framework).
Lua is a very cool scripting language.
"Both allow you to register methods and deploy as you need." That sentence applies to C, C++, C#, VB, SQL, DI Frameworks, JavaScript, General Motors, Ford, Hospitals...