In December, we wrote an Advisory about toolbar strategies employed by portals, IYPs and others. The benefit, in a nutshell, is to cement the brand into a user's browser, or desktop, which all but guarantees repeat use and exposure. The challenge, however, is competing for limited browser or desktop real estate. Google, Yahoo! and others have, as a result, enacted clever strategies and partnerships to drive toolbar downloads. Here is the latest one from Yahoo!.