This is definitely interesting. One thing to reemphasize (which the blog post says, but it cannot be overeemphasized) is that the sample size is so small as to make any results highly suspect.
The other thing I found interesting was this one:
>MCSE or other Microsoft certification
This makes sense. Getting an MCSE is a major investment in time and money in Microsoft technologies. Those people rarely also invest a lot of time learning nix as well (definitely some exceptions). I would not be surprised if many of those candidates simply moved on to other opportunities after finding out how tied to nix technoligies this particular job was going to be. Even if they were that person that had *nix skills in addition to their MCSE they probably found out they could make more money somewhere else that put more value on the certification itself.
The other thing I found interesting was this one: >MCSE or other Microsoft certification
This makes sense. Getting an MCSE is a major investment in time and money in Microsoft technologies. Those people rarely also invest a lot of time learning nix as well (definitely some exceptions). I would not be surprised if many of those candidates simply moved on to other opportunities after finding out how tied to nix technoligies this particular job was going to be. Even if they were that person that had *nix skills in addition to their MCSE they probably found out they could make more money somewhere else that put more value on the certification itself.