The MIT license scrunches the first two clauses of the 3-clause BSD license into a single clause, and omits the third clause (the nonendorsement clause, which is already generally implied). As a practical matter, most of the basic "simple" open source licenses are functionally identical.
But who owns the copyright to changes, and how is it recorded? I just am suspicious as to what or how large companies who sell/rent software deal with open-source, free stuff...
That's not covered by the license; that's covered by the CLA (Contributor License Agreement), and in the absence of one (I don't know if there is one or not for this repository), the author retains copyright to their code as usual.
