I'm using FF3 and I don't see what you're describing.

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> I do not know if anyone else is getting this, but I am on Firefox [Mozilla/5.0 (Windows; U; Windows NT 5.0; en-US; rv:1.9.0.1) Gecko/2008070208 Firefox/3.0.1], and when my cursor is stopped anywhere on the screen for Firefox, be it UT tab or another, the last tool tip I looked at shows up.
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> Since no one else as said anything, I suspect that this has to do with Firefox 3 and your changes.
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>Beth