The Yahoo Search Blog announced they have finally added support for the NOODP META tag. This allows you to override the SERPS behavior which would normally key off of Open Directory Project (ODP) (DMOZ) listings, or in this case, Yahoo’s directory listing. Read more
You can use this in two ways:

META NAME=”ROBOTS” CONTENT=”NOODP” (prevents MSN, Google and Yahoo from using ODP directory)

or

META NAME=”Slurp” CONTENT=”NOODP (prevents Yahoo only from using ODP directory)