This video will show you how to Jailbreak iOS 7 with Evasi0n on a Windows PC.
The Evasi0n iOS 7 jailbreak software has been released and you can watch the guide on the video above.
If you fast forward to 8:35 on the video you will see a bug where the icons have changed around and something has clearly gone wrong. A restore was the only way around this. Once I restore the device I was able to repeat the Jailbreak process again for a successful Jailbreak.
So I can confirm it does work fine.