Which strikes me as rather strange since I thought both of them would use Direct2D/DirectWrite as well by now. But demos like Scrolling Text [1] or animated text justification [2] leave much to be desired in Chrome and FF. The latter demo at least looks ok in Firefox.
[1] http://ie.microsoft.com/testdrive/Performance/ScrollingText/... [2] http://ie.microsoft.com/testdrive/Performance/TextJustificat...