Well, I remember them mentioning late November as a likely time to start shipping boards. You'll find some references to this on their [FAQ page](http://www.raspberrypi.org/faqs). We're in late December and they haven't even sold the beta boards (although that will probably happen soon). Manufacturing and actually shipping the first large series will take some time.

I'll agree that 'considerable' might be a bit too much, but they're late according to the initial schedule.