As noted many many times over in those ./ comments, the source article is full of holes. It's not just comparing apples to oranges; it's comparing apples to giant intergalactic apple-intolerant space monsters from Alpha Centauri.

All Unix-derived OSes are lumped together in a single category, the list includes third-party applications that about 3 people in the world use, the severity of the exploits is not taken into account, some bugs that affect both OSes (like Firefox bugs) are only listed under Unix when they apply equally to Windows, there are dozens of duplicate entries... the list goes on.

In short, the material is completely useless for any kind of comparison. Nothing to see here, move along.
In response to Crispy
Ah. I never noticed it counted third party aps. My mistake. Sorry, :(.
In response to Smoko
A quick scan of the comments would have told you as much! But you're forgiven... just don't do it again! Bad Smoko. ;-)
In response to Crispy
heh. I actually read around 3-4 of them, it was about how the linux vulns are patched quickly.

*Goes and crys in the corner*