The best thing to happen to Microsoft's public relations in years, Windows 7 is more than just spin. The latest official update to what some are calling the largest shareware trial period ever introduces more than mere bug fixes as the operating system upgrades from beta to release candidate. The Windows 7 Release Candidate does contain several major and minor changes, but the overall experience remains largely unchanged.

What's most important to you about the release candidate will depend on your perspective. Certainly, one of the biggest new features makes Windows Media Player useful again: you can now stream media files from one Windows 7 computer to another, across the Internet and out of network. Even better, the set up procedure is dead simple.

Windows Media Player now offers media streaming using your Windows Live ID. (Credit: Screenshot by Seth Rosenblatt/CNET)

When you open Windows Media Player, there's a new Stream option on the toolbar. Click it and you're presented with two choices. Both require you to associate your computer with your Windows Live ID. When you've associated a second Windows 7's WMP with that same ID, you can remotely access the media on the host computer.

A less glitzy but no less important change to how removable drives are handled also can impact your media. Unlike Windows XP and Windows Vista, Windows 7 will no longer AutoRun external hard drives and USB keys when they're connected. This kills off a risky vector for malware infections that has been the bane of many security experts.

Experts and people or companies who hope to use Windows 7 for business situations will appreciate the new XP Mode. It doesn't have much of a practical application for the home consumer, but if you need to access programs designed for Windows XP that have not been upgraded to Windows Vista or 7, XP Mode creates a virtual environment within Windows 7 that should assuage any fears of upgrading without backward compatibility.

It's not easy to set up once you've downloaded the XP Mode installer. You'll need to double-check that you have the right hardware and can get the right software. Hardware Virtualization Technology, also known as AMD-V, Vanderpool, or VT-d, must be supported for it to work. Motherboards older than two years probably won't work, and even if you do have a newer one you might have to go into your BIOS and activate Hardware Virtualization. CPU-identification utilities are available from Microsoft that can tell you if you're in the clear. However, if compatibility is the issue, this hassle will be worth it to you. Users will have full access to peripherals connected to their Windows 7 hardware, including printers, and the clipboard can be used to cut and paste between the virtual operating system and the "real" one.

Windows 7's native search feature has been improved. Files that I added to my hard drive were indexed so fast that they were searchable less than five seconds after saving them. Search result snippets now include a longer snippet, and highlight the snippet more clearly. This should appeal specifically to people who juggle large numbers of long documents, but I don't know of anybody who wouldn't appreciate finding the file they're looking for faster.

Lacking a touchscreen laptop, I wasn't able to personally try out the enhancements made to touchscreen support. However, it now supports multitouch zooming and taskbar previews when you drag your finger across the active programs pinned to the taskbar.

Search snippets make finding files easier in Windows 7. (Credit: Screenshot by Seth Rosenblatt/CNET)

Other changes stood out, too. Better Device Stage support for older devices makes one of Windows 7's best features applicable to peripherals and externals that don't need to be upgraded. Windows Media Player's mini mode looks much slicker, emphasizing the album art--sometimes at the expense of clearly seeing the controls, but it's a definite improvement. One annoying change is that Bluetooth support no longer comes baked into the operating system. If you need a Bluetooth driver, you'll either need the installation disc on hand or you'll have to download the driver.

Windows 7 continues to get better, but because this is the Release Candidate, unless Microsoft surprises us we're pretty much looking at the final feature set. If you're testing Windows 7 beta, you'll have to back up your data before upgrading to the RC, but once you do you'll be able to use it until June 1, 2010. The beta will start intentionally shutting down every two hours on July 1, 2009.

We've shot several videos at CNET TV about Windows 7. Among others, you can take a first look at the release candidate, a first look at the beta, which includes a lot of information about what you can do with Windows 7, and an explanation of how to dual-boot Windows 7 alongside your current Windows operating system.

Update May 6, 2009: Users who wish to purchase Windows 7 once the final version is released will need to do a full backup of their data and then perform a clean install of operating system. As with the update from Windows 7 beta to the RC, there will be no direct upgrade path to the final version.