Paul Thurrott from SuperSite for Windows takes a look at what the first service pack for Windows Vista will offer.
With that perfunctory background information out of the way, you're probably eager to find out what, exactly, is Windows Vista Service Pack 1. Certainly, there's cause for curiosity. Despite briefing me last year that Windows Vista SP1 would be released alongside Windows Server 2008 and would include a major kernel update, Microsoft subsequently launched a publicity campaign aimed at fooling customers into believing that the company hadn't yet even decided whether it would ever release SP1. Indeed, I sat and watched, twice, as Microsoft CEO Steve Ballmer publicly appeared confused about the mere mention of SP1, and he denied, both times, that the company was working on that release. The rationale for this decision, however dubious it may be, is that Microsoft was (and still is) quite concerned that its business customers will hold off on deploying Vista until SP1 is complete. That's because business customers have historically waited on the first service pack before deploying any major Microsoft OS release.