Are Microsoft's Support Plans for Win2K Affecting Your Decision to Move to W2K3?

I think you'll find a number of reasons it's worthwhile. There is a significant performance boost between W2K and W2K3. The hardware footprint is pretty much identical, so if you can shoehorn W2K into it you can install W2K3 as well.
Application compatibility is the sticking point, but if you upgrade a server rather than rebuild, I think you'll find the security for an application is a bit easier. And by now, pretty much all of vendors know their W2K3 compatibility; you'll certainly have to test but you don't need to start from scratch.

(TallSean is the author. The handle is an old joke between Sean Daily and I.)

My comment is to the anonymous user - i have 2003 installed on several older servers and found a performance boost compared to when these servers were running 2000 and nt 4.

Still running NT4 on some old server plateform apps are on lan and security on nt4 is now tight thank to the mistake of win2k and XP, Windows 2K will still be the mainstay for production server and workstation at my place.
moving to a new server ( clean install ) would require long test cycle for compatibility/ performance evaluation. maybe when we will buy a new server.