There's a lot of hate for Comic Sans, and it's not the fault of the font itself, but the fault of those who use it, and possibly because it's in MS Windows.

If life was fair, people would also be laying into the Chicago font ( http://en.wikipedia.org/wiki/Chicago_%28typeface%29 ) that ships with Macs, and that can still be seen on designs produced by crappy agencies. However, Apple-bashing is less cool than MS-bashing!

It's not the font, but what it was designed for (fun, on-screen - see http://www.connare.com/whycomic.htm ) and how it's been used (on signage, in print).

There's also the element of wanting to appear a font snob by picking the easy target of Comic Sans... As Connare himself said "If you love it, you don’t know much about typography and if you hate it you really don’t know much about typography either and you should get another hobby." ( http://www.manic.com.sg/blog/archives/000118.php )