If you make it work in IE7 you might not be far from IE6 support, because the two are near equivalent when it comes to support of the various javascript APIs. IE7 was mostly an improvement of the rendering engine. (Note that there are supposedly small inconsistencies between IE7-mode in IE8 and the actual IE7.)

That said I have a vested interest in IE6 dying quick, so I fully support a decision to not support it.