Visual Editor broken – tinyMCE not defined

My Visual editor is broken. It does not work in either Firefox or IE. In my Firefox Error Console I’m seeing two problems with TinyMCE:

tinyMCE.getInstanceById is not a function

and

realTinyMCE is not defined

I’ve tried disabling all my plugins, but it doesn’t help.

The problem is being tracked here. It is marked as fixed with but it is not resolved for many of the commenters. The version of tiny_mce_gzip.php offered as the fix did nothing for me. Is anyone else experiencing this??? Need to get this resolved!