Staring on March 1, 2010, Facebook apps will no longer be able to send users notifications.

You've likely been receiving a few last minute notifications from many apps letting you know they cannot reach you any longer via notifications - such as the screen shot from the Chinese Horoscope app below (oops, forgot I even installed it. Lol!)

Facebook apps CAN contact you via email - IF you choose to opt-in. Each app will need to ask your permission independently. See screenshot of Networked Blogs app (one of my TOP picks!!) below.

This change is really rather significant for app developers and not so much for users.

See this post on the Facebook Developers wiki - excerpted here (remember, this is for Developers):

You can use email to communicate directly with your users. Send email to your users to inform them of interesting and important information, like receipts for purchases they make, messages to help reactivate them if they haven't visited your application or integration in a while, or newsletters promoting new features or contests.

When the user grants your application or site the email extended permission, you receive either the user's primary Facebook email address (the address where Facebook communicates with the user) or a proxied email address. The user chooses which one to share when the user sees the extended permission dialog.

See also Mashable's post here Facebook to Say Goodbye to App Notifications on March 1st.

So, will you be giving your email address to all apps? Just ones you use a lot? Let me know in the comments below: