App developers know that Facebook’s restrictions on application emails have made the use of email as an effective communication channel much more challenging. Tonight, there is good news: Facebook is announcing several new features for developers to employ in their application emails.

Here’s a quick summary:

1. Many new formatting tags are available for the first time. For a complete list of which HTML tags developers can use in their emails, see the Developer Wiki page.
2. Demographic restrictions are now available in email through FBML
3. Personalization is now available in subject lines through FBML (“Justin, your latest updates…”)
4. Internationalization tags are also available through FBML for those who have translated their apps
5. Daily email limits are gone for users who explicitly granted email permission to your application. The allocation limits still apply to all users who added the app before the redesign.

While there are still some restrictions in place, these new features will certainly allow developers to send richer, more engaging application emails, which should benefit everyone in the ecosystem.