A note for anyone wanting to use Build.PL and provide a Makefile.PL, please be aware of the conflicts. If you use a Makefile.PL, don't have it write a Makefile...
This comment must be based on old information. There is currently no problem with Makefile.PL generating Makefile.
... just have it print a message saying use Module::Build and run perl Build.PL
No! This then forces the user to have Module::Build installed.
If you don't want to support a Makefile.PL script in your distribution, then just don't put one in it. Or better yet, make use of Module::Build's capability to generate a Makefile.PL script.
Remember: There's always one more bug.