From the responsive typography O'Reilly book
A good 'Flash of Unstyled Text' demo - original source at http://rwt.io/resources/code/responsive-typography-book-sample-code
This demo shows how to handle the delay in the arrival of Web fonts to the browser. The technique revolves around the idea of as closely as possibly configuring alternate fonts to resemble the look and behaviour of the 'yet to load' web fonts.
One undesirable behaviour when waiting for web fonts is the reflow effect caused by the difference in word spacing - this demo shows how to mitigate or remove this effect.