From some of the problem reports in Blogger Help Group: Login Issues, it appears that some login scripts may have been changed again.
As in Blogger Alert 12/2: Missing Toolbar Buttons, if you're having any problems logging in, or if you're missing your blogs in your dashboard, you might want to try clearing cache and cookies again.
(Edit 1/31): The bX-68tbuv problem with image uploads, which appears to be related to this issue, has been fixed. Here's a definition of the lack of uniformity of the problem - this specific problem was unique to sessions starting from "beta.blogger.com".
This has been fixed. Regardless, use www.blogger.com and not beta.blogger.com.