Well I think it's a mixture of both, "disproportionate coverage" is a fair description, insofar as it misrepresents the activities and opinions of the research community (most of which appears to consider it hokum). I'll have to defer to the experts for the details, however, as I'm merely relaying their concerns.
I watch Sixty Symbols on Youtube and they have a number of episodes on string theory--which I've read necessarily implies extra dimensions(can't vouch for that conclusion personally), leading to multiverse theories. These episodes are straight from researchers themselves so I was surprised to read these ideas in the link provided, supporting your idea that the multiverse is hokum.
