I have concluded that the world is divided between MS Comic Sans lovers and haters. I am currently among the haters, but I have been among the lovers at times.
Objectively, there is nothing wrong with Comic Sans. It’s clear, easy to read. It’s much better than anachronisms like Courier New, whose spindly lines are artifacts of manual typewriters that had to concentrate the impact of keys into narrow lines in order to make a clear mark on the paper. Although it radiates light-hearted casual, there is sophistication in the shaping of those rounded forms.
Most of the time, I prefer a serif font like Times New Roman. Those clever medieval scribes had something when they added those little flourishes. A serif font is a climbing wall with lots of hand and footholds, something for the eye to grab hold of as it makes its way down a line of text.
Comic Sans is too slick. My eye loses its place too easily. Not a big deal, but enough to make reading Comic Sans a chore to read rapidly.