Not sure what is going on here, but my Google Webmaster account turned back 82 404 crawl errors. Upon further investigation, some of the URL's are being rewritten somewhere along the lines to the following (an example).
Some have email addresses added to the end, some blog posts have additional directories added, etc.
For SEO, I'm using the All in One SEO Pack, but everything looks fine there. Robot.txt looks good, and so does my .htaccess file. Anyone have any ideas?