If you’re a Windows Phone developer and want to get your apps ready for the next OS release, then pay attention. Microsoft has been heavily criticised for not having the Windows Phone 8 SDK available while WP8 devices from Samsung and Nokia are being shown off.
While WP7 apps will run on WP8, there are new benefits (some not public), others like NFC, that developers will want to implement into their apps. For your chance to get in early, you can apply for the preview at the Microsoft Connect site.
Given everything is hush hush right now, you will need to agree to a non-disclosure.