MSYS is much more workable than Cygwin, but it's still not a panacea. More of a placebo really.

But most web designers would be slicing PSDs at some point, right ?

And Cygwin is a joke. Dealing with the page separator differences alone would make it unbearable.

I believe Aderkent meant that many web developers who are not designers (e.g. me) have no need of Photoshop - so we don't use a Mac.

By the way, Gimp can open psd files. I'm not sure it works perfect though.