UPDATE: Thanks to the helpful tips from several readers. The problem seemed to be with how Site Meter interacts with IE 7. A simple change in the privacy setting on Site Meter seemed to resolve the problem.
Starting yesterday, Sitemeter has caused thousands of blogs to fail in Internet Explorer 7 for some reason. Both Hot Air and Michelle Malkin sites have been affected. According to Charles Johnson, the problem exists on Sitemeter’s own website. It appears that Sitemeter changed its coding yesterday without warning its users, and without testing it before going live with the changes.