These people may have a lot of errors when it all boils down to typing in keywords when they do most of their searches on the most widely used search engines. But you should take the necessary steps so as to exploit their errors and to fully tweak the ranking of your internet site.
Misspelled keywords are so usual you'd think most of the people on this planet don't know what the hell they're all looking for, and more so, what they want! So if you have an internet site to run, you should include these misspelled keywords on the actual META tags of each page of your internet site.
