Its ok, Im allowed to talk about SP1.  I know alot of you have been eagerly anticipating any information about SP1 so here it is.  Updates in Windows Vista SP1 fall into 3 areas - Quality Improvements (Reliability, Security and Performance), Improvement to the Administration experience including BitLocker and finally support for emerging hardware standards such as Extensible Firmware Interface (EFI) and an Extended File Allocation Table (exFAT).

One area I am looking forward to is the Performance Improvements and it looks like there are going to be quite a few areas of improvements to look forward to.  The following list describes some of the performance improvements that Windows Vista SP1 will include:

• Improves the speed of copying and extracting files.
• Improves the time to become active from Hibernate and Resume modes.
• Improves the performance of domain-joined PCs when operating off the domain; in the current release version of Windows Vista, users would experience long delays when opening the File dialog box.
• Improves performance of Windows® Internet Explorer® 7 in Windows Vista, reducing CPU utilization and speeding JavaScript parsing.
• Improves battery life by reducing CPU utilization by not redrawing the screen as frequently, on certain computers.
• Improves the logon experience by removing the occasional 10-second delay between pressing CTRL-ALT-DEL and the password prompt displaying.
• Addresses an issue in the current version of Windows Vista that makes browsing network file shares consume significant bandwidth and not perform as fast as expected.

Here are some more resources:
This is the press release
Here is information regarding SP1 Beta
Windows Vista SP1 Beta Whitepaper

What is SP1?  What is it not?
In addition to updates we’ve previously released, SP1 will contain changes focused on addressing specific reliability and performance issues we’ve identified via customer feedback, supporting new types of hardware, and adding support for several emerging standards.  SP1 also makes additional improvements to the IT administration experience.  We didn’t design SP1 as a vehicle for releasing new features; however, some existing components do gain enhanced functionality in SP1.

More information on what’s included in SP1 can be found in the detailed white paper.

When can I get my hands on the Beta of SP1?
A Beta release of Windows Vista SP1 is slated for availability in the next few weeks.  A small group of testers has been putting a preview of the SP1 Beta through its paces to help prepare for broader release.  We made the choice to start with a very small group of testers because we think it’s better for both our customers and for Microsoft to keep the beta program small at the start.

A later pre-release of SP1 will be available to a larger group of testers  via MSDN and TechNet subscribers.

And what about SP1 itself -- when will that be available?
We're targeting releasing SP1 to manufacturing in the first quarter of 2008, but as always, we’re first and foremost focused on delivering a high-quality release, so we'll determine the exact release date of SP1 after we have reached that quality bar. (FYI, in case you didn’t already know:  the Windows Vista SP1 and Windows Server 2008 engineering efforts are aligned, so the Server team also said on their blog today that they are targeting the first quarter of 2008 for their release to manufacturing.)