What surprises me is that these magazines don't change to an online format. Their problem is not that they're not viable, but that traditional print journalism is not viable anymore. Anyone in journalism will tell you that it's been brutal the last couple of years even *before* the economy tanked. This is a question of the kind of business model (I hate that term to death, but it applies here) you're using.
With advertising down I'm sure it's tough to keep an online version of Metal Maniacs and Metal Edge (to be honest Metal Edge was always a piece of shit, and I was surprised to hear it's still going). But that's the way these magazines have to go if they want to survive... if newspapers are having to do it, you'd think magazines would get smart and do it, too.
I'll be sad to see Metal Maniacs shut down, for sure. It was one of my favorite magazines, even if the Aural Assaults reviews were sometimes uneven (and they adopted the very irritating and subjective criticism of "song distinction" on albums in their reviews). This is really random, but I remember one of their late 1990s reviews of Virus 7's debut album (produced by Mercyful Fate's Hank Sherman)... it was the funniest and most brutal review ever. I can't remember too much about it 10 years later, but it was the first time I saw a reviewer put the word "riff" in quotation marks as a form of criticism.