I upgraaed to 2.6 - I created a new directory, unpacked all the files from the tarball, copied over my plugins and themes, and now I get --- nothing.
So I ran the upgrade script. It ran and now I get --- nothing.
Humph. I ran wp-admin/admin.php. I get --- nothing.
Blank page. No errors in the log files. I removed my cutline theme, thinking that might be it. Nothing. Blank page.
I look at the source code - I get nothing. AFAICT WP2.6 is sending out nothing but totally empty pages.
Sorry I can't be more help but I am stumped. Where do I start?