Yahoo's search has been updated with a "suggest" feature that brings up search queries it thinks you're looking for based upon what you type. Previously, the only way to get Yahoo search suggestions was with Yahoo's Firefox toolbar.
The company is promoting this new suggestion service as a way to speed up search. For people who struggle with correct spelling, suggestions can save a page load or two when a mistyped name yields the helpful, yet mildly patronizing "did you mean" message.
The new suggestion service is nearly identical to Google's; however, Yahoo users don't get the added benefit of seeing how many search results each query has.