Please, if you are a module author using Module::Build, make your work compatible with the tons of things out there that expect a normal perl install process by changing this one thing in your Build.PL and including the generated Makefile.PL in your distribution. If you someday start using actual features of Module::Build that are not supported by MakeMaker, you can change it then.
Since nobody else seems to have said it, and speaking as a fan of Module::Build, I agree completely :-) There is little point in foisting Module::Build on users unless you're using features not supported by EU::MM.
I have to admit that I've not come across a CPAN module that uses M::B that doesn't have a generated "traditional" Makefile.PL. Has it been a common problem for you?