Today is the official Windows 7 Launch Day! A lot of us have been using the operating system for quite some time now, either in release candidate form or retail form, and the buzz on the street is mostly positive. I've gone as far as to say it's the best operating system ever released. Why? Well, here's 10 things it does that no other operating system can do.

1. Homegroups: File sharing is notoriously difficult in Windows, and can even be a chore in Mac OS X and Linux if you're not using a supported router. Homegroups are the easiest way to share files around your network, ever. I recently helped a friend setup a Windows 7 network, and we found that once the Homegroup is setup, you simply right-click on anything you want to share, hit "Share with Homegroup" and then select if you want read access only, or write access also. Go to another machine and it'll be right there waiting in the Homegroup.
2. Libraries: From the get go, you'll notice that your music, documents, photos and videos are arranged into predefined Libraries, but you probably won't know why unless you look at a little drop-down in the top right of the Library's window. There's a new option in there simply titled "Arrange by:". For your photos, this gives you month, day, rating and tag. Tag is the important one there, as you can tag your photos with terms like plants or friends, and they'll all be right there at your fingertips. Hopefully Office 2010 will incorporate tags also, so you can have a clients library and use tags to separate them. No more annoying folders!
3. Backups: Granted this was really a Vista feature, but it never gets enough attention. The backup system in Windows 7 is so simple to use, and it can put your backups anywhere since they're simple files. This means an Apple Time Capsule, Linux Samba Server, or Server 2008 machine, just to name a few examples. Backups are incremental and easy to restore from to.
4. Windows Media Center: This is the only way to view TV in my opinion, and soon we'll have full Cablecard support without having to hack around the OCUR BIOS restrictions. Just install a tuner, call your cable company and setup an install, then watch full HD straight into your system. Even share those recorded shows with other TVs over your network using Extenders or other PCs. No more recording the same show twice to watch it in two rooms.
5. Jump Lists: I find myself using this feature more than just about anything in the user interface overhaul. You can right-click on Internet Explorer and pick out where you want to go. Mouse over Notepad and see a file you just closed. Or, mouse over Media Center and select the episode of The Daily Show you want to watch.
6. Games: Not only does Windows 7 support playing the latest DirectX 10 titles quickly, it also brings DirectX 11 which is destined to be adopted by developers much quicker than DX10 was. Functions like the tessellator and geometry shaders are already bringing more realistic images in games like STALKER and Battleforge.
7. Multi-touch Support: Every major player in the notebook game is releasing a multi-touch laptop to ship with Windows 7, and the age of the multi-touch tablet is here. Even desktop monitors are coming with multi-touch support, although I'm really waiting for a tablet like a writing tablet with it. Windows 7's support for these devices makes that idea possible, and soon we may be typing on multi-touch interfaces instead of keyboards.
8. Windows XP Mode: While Apple requires you pay for Parallels or Fusion to run old Windows applications, Microsoft bundles it right into Windows 7. Run any old Windows XP application natively, with not compatibility issues.
9. Action Center: Since Windows is handling all of your important functions like backup, antivirus, and updates, there's a single place to see the status of each of these components. The Action Center is a polite flag icon next to the clock that only pops up when there's an issue. Easily turn off notifications for things you don't care about too.
10. Troubleshooting: Now even better in Windows 7 is the troubleshooting section. If a problem occurs that's been fixed already, Microsoft will tell you explicitly how to fix it, even if it's not their fault. They provide links to other manufacturer's updates and drivers to get your machine working just like it should.