In an email sent out to registered developers, Microsoft introduced overlay badges that can be added to screenshots of their apps to show that they are Mango-ready.  The "New for 7.5" icons will indicate that an application is optimized for Mango, and will be the only graphics of their kind that will make it through certification.  The email urged developers to getting cracking on updating for WP 7.5 and utilizing its exclusive functionality, such as multiple live tiles and fast application switching.

Microsoft pointed out that Mango devices are already available in Japan and Russia, with more on the way (very soon!).  And despite an earlier edict that updates would not be allowed to 7.0 versions of apps once their 7.5 counterparts were released, it was announced that that would no longer be the case.  By popular demand, Microsoft will enable App Hub functionality which will allow devs to update both 7.0 and 7.5 versions of their products come the end of October.

You can click the thumbnail below for the full content of the email, which further descibes the update process.

You can download the overlays here.

Source: Microsoft; Via: WPSauce