Description of problem: In recent versions, localinstall is simply an alias of install in my understanding. This should be documented in the man page of yum.
They aren't the same. It is documented that install will do a localinstall if given a local filename that ends in .rpm. localinstall won't do any of the features of install though, and (at least in theory) can install "abcd" if it's an rpm (it doesn't check for ending in ".rpm").