While UAC has gotten most of the attention during Windows Vista's tenure, the runner up for most discussed Windows Vista feature is probably BitLocker. It seems like a week doesn't go by without some sort of major compromise of sensitive data resulting from a lost or stolen laptop. BitLocker guards against these types of data security breaches by providing whole disk encryption, protecting all of the data on the hard drive and preventing unauthorized users from accessing it even if they happen to be in possession of the laptop.
Initially, BitLocker would only encrypt the root operating system drive. However, with Windows Vista SP1 BitLocker functionality was extended so that other drives or volumes could be encrypted as well. In Windows 7, the next generation operating system currently in Beta release, Microsoft adds BitLocker-to-Go, the ability to encrypt data on USB thumb drives and other removable storage devices. The Microsoft Springboard team have put together a screencast explaining the BitLocker and BitLocker-to-Go functionality in Windows 7. The Windows 7 Walkthroughs also cover other Windows 7 features such as AppLocker, PowerShell 2.0, and more.
It’s a great feature, too bad it’s limited to Enterprise and Ultimate versions. If M$ was really serious about security then bitlocker and applocker would be moved all the way down to Home Premium.
Granted, I concede there is a lot of potential for “pain” when the “average” home users lose their passwords/keys. But then again they were initially concerned about firewalls, which is why the started off with the crippled “inbound-only” firewall.