Chrome loses your preferences - gah.

http://saravananthirumuruganathan.wordpress.com/2010/05/10/how-to-solve-your-profile-could-not-be-opened-correctly-issue-in-chrome-or-chromium-without-losing-your-profile/

Restored from backup /Library/Application Support/Google/Chrome/Default/Preferences

Create a new browser user profile:

http://support.google.com/chrome/bin/answer.py?hl=en&answer=142059

(which I didn't do.)