I haven't done an "official" test yet (it's on the list - like everything else

), but beginning with IE 8 RC 1 and with TD 2.5.6, everything appeared to be working fine. Once IE8 hit release candidate 1, the only thing I had to change was some UI spacing to fix some graphical artifacts that appeared on dialogs and such. All of the other "problems" just went away once IE8 got out of beta.