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Turns out it happens when you set the place holder PlaceHolderPageTitleInTitleArea with Visible attribute false.
The solution, for Travis Mathison, is to wrap the placeholder in a panel, linked with a css visibility attribute set to false instead of doing it through the place holder attribute.
Although Travis saved my life by finding this solution, I worked out my own through his, and now you don't need an external css file, and the white-space occupied by the place holder won't show up.
Note: SharePoint 2007 works great either way. My solution in IE for SharePoint 2010 still shows some text on the bottom of the page. Anyway, I decided not to hide this place holder, since it gives some context options for lists and such, and won't be available if the place holder is removed from the page.