I don't know if this is by design or a bug, but I can't use icon templates when editing library banner icons. Trying to use a template causes the text to be repositioned incorrectly.
(As an aside, weren't there a few templates included with 2009? For some reason mine went MIA.)
It's not just templates. It looks like the IE tries to use the banner size as the full icon height so that it will do the vertical centering of the text correctly. However, any interaction with the icon other than entering text in the text tab causes the vertical centering of the text to be messed up (and not always as nicely as you got. It seems to depend on where you click).