Here are some popular webcomics placed against the top three print sellers for July 2008:
xkcd - 465,000 unique visitors
Secret Invasion #4 (Marvel) - 175,500 sold (top print comic for the month)
Cyanide and Happiness - 260,000 unique visitors
X-Men #500 (Marvel) - 152,000 sold (2nd highest print comic for the month)
Penny Arcade - 199,000 unique visitors
Astonishing X-Men #25 - 110,700 sold (3rd highest print comic for the month)
It wasn't long ago that people laughed at the notion of a webcomic outperforming the X-Men by more than two to one. I'm not sure who those people were, but I'm sure they exist.
In fairness, these particular webcomics do not require much financial or time commitment from a reader.
I'm interested to see what will be the first comic book style webcomic to reach comparable numbers. Girl Genius is a contender, getting over 200,000 visitors/month, but when you reduce it to unique visitors, it's more like 25,000. That would tie it with DC's Batman Confidential #19, the 98th best selling print title in July.
I also note that print sales have been slipping this year, while most of the webcomics I've examined have shown gains. Even growth of 25 or 50% is not unusual.
Sources: Alexa, Compete, icV2.com
