This all illustrates the mindset that individual home users as well as a large percentage of IT professionals have of automatically adopting a new system after the first service pack, but never before. It also illustrates why Microsoft is expected to push out a service pack so soon after the original OS release with no significant changes or improvements. (Microsoft lacks a lot in their development abilities, but they have a marketing organization second to none.)
edit: If an organization has a Windows 2000 system functioning for themselves, why would they give up the stability offered by that OS for a new one that offers a significantly lower level of stability?