I want SP1. But what's in it?

Microsoft spells it all out in a change log-style document posted on its TechNet site. It's a must read.

Six months ago, the company broke down the contents of SP1 into three categories -- reliability and performance updates, administrative improvements, and new support for some newer standards -- but the company has expanded that list to include application compatibility and interoperability improvements, as well as several items that should come into play once Windows Server 2008 rolls out.

Among the bits that Microsoft has trumpeted loudest are performance improvements in copying files and browsing network shares, minor speed increases in resuming from sleep or hibernation, better luck connecting computers via ad hoc wireless links, and a reduction in the number of crashes.

Here's one interesting claim: "Early SP1 tests show Microsoft more than doubled the mean number of hours between 'disruptions' as compared to RTM." Microsoft didn't define "disruptions," but we assume they mean work-stopping crashes and lockups, maybe even slowdowns so dramatic that a reboot is the best bet.

By definition, SP1 also includes all the updates, patches and nonpatches that have been released between Vista going RTM late last year and now, or whatever "now" Microsoft is using as its cutoff date. That cutoff date appears to be October 2007, which means that several patches for critical vulnerabilities disclosed in both December and last month didn't make it into the service pack or its testing process.

For more information on the specific changes in SP1, watch for our next FAQ, which will detail some of the more interesting update angles.

Is there anything I have to do before installing SP1?

There are three prerequisite updates that must be in place before SP1 can be downloaded and installed. The three files were pushed through Windows Update during last month's regular security session on Jan. 8, so users who had Automatic Updates set to automatically download and install should already have them. If they're not installed, SP1's process takes care of them for users, but it adds time and multiple reboots to the deal.

Some Vista users were incorrectly fed one of the three updates in January. Then, Microsoft sent a fix for BitLocker, the full-drive encryption technology bundled with the premium versions, to everyone, including PCs running Vista Home Basic and Home Premium. But Microsoft said there was no harm and thus no foul.

Oh, and yeah, about those blocking drivers -- there's not much users can do there, at least according to Microsoft's Nash, who essentially told everyone to just sit tight and wait it out. "As updates for these drivers become available, they will be installed automatically by Windows Update, which will unblock these systems from getting Service Pack 1. The result is that more and more systems will automatically get SP1, but only when we are confident they will have a good experience."

Why all the fuss about a service pack?

Although Microsoft claims that Vista has done a 100 million-copy business in its first year, the buzz -- especially in the past six months -- has been more about what's wrong with the operating system than what's right. SP1 is an opportunity to bring back the buzz, or at least stem some of the complaints, a fact that Microsoft tacitly acknowledged in both the early-rather-than-later release and in a presentation it recently used to tout the update.