Microsoft's offering anyone who signs up to be notified of when they can pre-order Windows Phone 7 -- "all you need to do is write them an email, and follow through with the pre-order once it's announced then you get your three months of Zune Pass for free. Please note It's only available to those in the United States."
Zune Pass is a subscription based music service that allows users to download an unlimited amount of music, and keep listening to it as long as they keep paying the monthly rate of $14.99. Comparing to other popular music services that charge $1 per song, it isn't too bad of a deal.
Microsoft that you confirm you'e going to buy a phone now, and then follow up later with a pre-order of WinP7. Find out more at Microsoft's Store page, and enjoy the music!