The first Vista service pack may serve dual purposes for Microsoft: fixing the operating system's rough edges and, simultaneously, indicating that it's ready for mass adoption.
Microsoft initially downplayed the importance of service packs in an era where patches are easily available online. Also, the company urged businesses not to wait for a service pack to start testing and rolling out Vista.
http://news.zdnet.co.uk/software/0,1...9288961,00.htm
Note that XP SP3 is also due next year....