So What Is New In XP SP2 RC2?

There's no list of new features in Microsoft's Windows XP SP2 RC2 Fact Sheet. But they have confirmed some changes.

Microsoft hasnt said much publicly, in terms of the feature tweaks it made between the March Release Candidate (RC) 1 beta of Windows XP Service Pack 2 and the RC2 variant that it made available for download this week. Theres no list of new features in the RC2 Fact Sheet. But members of the XP SP2 dev team confirmed the validity of our short list of tweaks that Microsoft was slated to make between RC1 and RC2. The biggest of these: MIME sniffing is now turned off by default.