the PPC Book|Pay Per Click Blog | Long Tail Thoughts in a Short Tail World

Yahoo announced Friday that they upped the limit from 50 to 250 for excluded, aka, negative keywords:

Excluded keyword limits have increased from 50 to 250 to help relevance

• Go to your Ad Group Settings page.
• Click on “Tactic Settings.”
• On the “Tactic Settings” page the “Excluded Words” feature is displayed.
• Click on “Excluded Words” to open the entry field.
• Add your excluded words but do not to use any commas or semicolons after each word.
• Click “Save Changes,” to process the Excluded Words list.

By all means, take advantage!