Why not it's a tried and tested platform that will be around in large companies for some time and is supported for another 5 years. I contacted QCA the other day and it seems their exams software 'should' support 2008 soon. I'd recommend 2008 DC's now on a new build but if you need 2003 member servers I can see no reason not to use it. It's an excellent platform with low hardware requirements and it virtualizes pretty well.
Is it sensible that people are still recommending 2003 for new vanilla builds?