[wp-hackers] Seeking some advice

[Malaiac]

my 2 cents
'new role' for your users

on the post-new form, restrict the categories box to show only the right
category, or better remove the categories box and add a hidden input
on the save_post hook, make sure that a post by this 'new role' is assigned
to this right category (double check)

exclude the category from your regular loop (no need to manage exclusion on
authors' list)

use /author/ page to show their posts, with a trick on URLs
on the author_link (not the right name) hook, rewrite :
 regular wp editor : /author/john
 happy few who get a column (based on their 'new role') => /column/john