It doesn't really look like it: I can't see anything in the Internet Explorer 9 Beta Guide for Developers. True, it's not the final release yet, but you'd expect to see something about it in the Beta version if they were going to support it....
caniuse.com says "support unknown".
与恶龙缠斗过久,自身亦成为恶龙；凝视深渊过久,深渊将回以凝视…
