Today comes a new dawn for search engines with the first-ever Beta launch of 'Dynamic URL Rewriting' in Site Explorer. The new feature provides the ability for site owners to alert Yahoo! of the dynamic parameters in URLs that they'd like Yahoo! to ignore, which we'll then automatically rewrite accordingly. Try this out for all the cases where you'd want to use parameters in your URLs that don't affect the content of your page, but that have other important uses.