I haven't tried this on the Facetime icon, but I highly doubt it'll work.

The Brooks Review on the iOS notification system:

How do you design a notification to simultaneously be annoying and alerting, while at the same time getting of the way when it needs to get out the way. That is, to say it better: how do you design a notification that notifies you and reminds you of things, all the while it doesn’t annoy you and notify you about erroneous stuff? Is it even possible?

As I previously mentioned in my comment here, not all notifications should be treated the same.

Alerts that require immediate action (a Skype call for example) should use modal popups or other methods that interrupt the workflow. If the user is not okay with that he should be given the option to disable them selectively (or all at once) in the settings. Notifications that inform users of incoming data (IMs, emails etc) / background tasks completion should not interrupt the workflow. They can be stacked somewhere (for a given period of time) or completely disabled in the settings.

Over the months that Camera+ has been out in the wild, we’ve observed many, many people using the app in the real world. One thing that initially surprised us was to learn that most people had no idea that multiple photos could be selected in the Lightbox. Even though we mimicked the way Apple set things up in their Photos app, it soon became obvious to us that this function was less than obvious to our users, unfortunately.

Regardless of the fact that Apple did the exact opposite of what it recommends in the HIG, using the same icon for two distinct actions is downright reckless.

Some suggest that @ has its origins in the sixth century, when monks adopted it as a better way of writing the word ad-Latin for “at” or “toward”-that was not so easily confused with A.D., the designation for Anno Domini, or the the years after the death of Christ.

A good read if you can put up with ugly gloss and over-contrasted gradients.