The Facebook developer blog has a post entitled Change is Coming which details some of the changes they've made to the platform to handle malicious applications including

Requests

We will be deprecating the notifications.sendRequest API method. In its place, we will provide a standard invitation tool that allows users to select which friends they would like to send a request to. We are working hard on multiple versions of this tool to fit into different contexts. The tool will not have a "select all" button, but we hope it enables us to increase the maximum number of requests that can be sent out by a user. The standardized UI will hopefully make it easier for users to understand exactly what they are doing, and will save you the trouble of building it yourself.

Notifications

Soon we will be removing email functionality from notifications.send, though the API function itself will remain active. In the future, we may provide another way to contact users who have added your app, as we know that is important. Deceptive and misleading notifications will continue to be a focus for us, and we will continue to block applications which behave badly and we will continue to iterate on our automated spam detection tools. You will also see us working on ways to automatically block deceptive notifications.

It looks like some but not all of the most egregious behavior is being targetted which is good. Specifically, I  wonder what is meant by deprecating the notifications.sendRequest API. When I think of API deprecation, I think of @deprecated in Java and Obsolete in C#, neither of which prevent the API from being used.

One of my biggest gripes with the site is the number of “friend requests” I get from applications with no way to opt out of getting these requests. However it doesn’t seem that this has been eliminated. Instead an API is being replaced with a UI component but the API isn’t even going away. I hope there is a follow up post where they describe the opt-out options they’ve added to the site so users can opt-out of getting so many unsolicited requests.

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