Fatal error

I was updating my site with 3.0.1 and it completed and my internet whent down and now I get this Fatal error when looking for my site https://www.amrarmament.com

Fatal error: Call to a member function add_rewrite_tag() on a non-object in /home/amrarmam/public_html/wp-includes/taxonomy.php on line 289

And to top this off I can no longer login under my “real” user name.

Thanks.
man I feel sick…