This is not present in all form text items, but there are some cases where the text is aligned to or closer to top (only in Firefox).
Here is a problematic case: http://i.imgur.com/LHBbX.png
TESTED with Firefox 9.0.1
Yup, not much we can do about that—that's just the way some browsers are going to interpret this kind of stuff without boatloads of custom and hacked CSS. Not always possible :.