Ranking well in one search engine doesn’t guarantee success in another. Often there are huge differences in results between Google and Yahoo for example. Want to see for yourself? Check out a new website called “Thumbshots Ranking Tool” which allows you to compare results between the different engines.
Search Engine Watch explains how it works: “URLs are represented by small circles, and these circles are connected by a line if the page appears in both engines you’re testing. Mouse over a circle and the full URL of the page is displayed.”