This text at the top of the new html and aspx page templates that visual studio .net beta 2 creates by default, has some interesting side effects.
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.1//EN" "http://www.w3.org/TR/xhtml11/DTD/xhtml11.dtd">
One of them is to cause table heights of 100% to stop stretching to the full size of your browser, and to wrap to the table contents instead.
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More about the use of doctype in Sharepoint here...
http://heathersolomon.com/blog/archive/2008/01/25/DOCTYPES-and-SharePoint.aspx