Thursday night, last week, the Yahoo! Search Blog wrote Yahoo! Search Crawler (Yahoo! Slurp) - Supporting wildcards in robots.txt. I am honestly a bit shocked by the SEO community's response to this, or lack thereof.
I have spotted two threads on the topic, both just threads that say, that Yahoo! announced it and nothing more. I know this is something Webmasters have requested in the past and that they have looked down upon Yahoo! for not supporting until now.
The two additional parameters include:
You can now use '*' in robots directives for Yahoo! Slurp to wildcard match a sequence of characters in your URL.and
You can now also use '$' in robots directives for Slurp to anchor the match to the end of the URL string.
More details at http://help.yahoo.com/help/us/ysearch/slurp/slurp-02.html.