@font-face is definitely a huge string to the CSS author's bow, in fact, it's like a freekin' flamin' arrow, but watch out, Safari isn't very nice to slow connections.
I recently peaked my total broadband usage and as a slap me down, my ISP, Plusnet, put me on about a 6Kb connection. Which sucks. Web pages are slow, email is slow: it's slow.
This was the sequence of events I saw in Safari as the browser downloaded the
I've run the same test against Opera 10b and Firefox 3.5b and both render the text out, and only once the font has been downloaded, do they then re-render the text, here's Opera (I also captured Firefox, but the heading is clearer in Opera for this example):
I'm not sure if that first screen is the FOUC bug - I didn't think it was...
The real issue for me, is the simple fact the text is missing. It's not that unique that I'm on a slow connection. It's slow when I'm using my 3G dongle. It's slow when my laptop is tethered to my iPhone. The more we use mobile telephony to do wireless connectivity, the more we're going to see slow download speeds (certainly for the next few years). We need to keep in mind those slow connections are out there as real users, and not just some family farm in the middle of The States somewhere.
Oh, and Webkit should fix that bug!