I have always avoided paying attn to yahoo and more so msn but when you end up with a site that has no traffic and rely on those two engines you have no choice...anyway they also have a verification process which I didnt know about till recently and works similar to google's webmaster tools except it also gives a rating on your pages, pages that link to you, your outbound links, 404 pages etc...its actually not that bad to see what issues the other bots might be having besides google.
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