I just updated my cvs tree this morning and saw the following when loading a test blog page like "/index.php" instead of just "/":
Warning: strpos(): Empty delimiter. in wp-blog-header.php on line 36
The only difference from the cvs update is Ryan Boren's change to wp-blog-header.php to use strpos() instead of preg_match() so this must have caused the regression.
Addtionally, I saw this when loading wp.php:
Warning: Invalid argument supplied for foreach() in wp.php on line 21
Of course, this may just have to do with the test blog not having any posts.