This is a Hoax. Not true. Fake.
This was created just to make people forward it.

Think about it:
If Facebook is getting slow, it is because everyone is forwarding this fake message to all their friends.

And, if Mark Zuckerberg wanted to send a message to see if you're active, he could easily do it without your/our help. He would automatically send a message to everyone himself.
Or better yet, he would just check the log files and see who hasn't logged in a long time.
He doesn't even involve himself in the workings of Facebook anyway.

UPDATE: But most of all, he would spell his last name correctly. ZuckerburG.

Below is a copy of the message.

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Attention all Facebook members.
Facebook is recently becoming very overpopulated,
There have been many members complaining that Facebook
is becoming very slow.Record shows that the reason is
that there are too many non-active Facebook members
And on the other side too many new Facebook members.
We will be sending this messages around to see if the
Members are active or not,If you're active please send
to 15 other users using Copy+Paste to show that you are active
Those who do not send this message within 2 weeks,
The user will be deleted without hesitation to create more space,
If Facebook is still overpopulated we kindly ask for donations but until then send this message to all your friends and make sure you send
this message to show me that your active and not deleted.

Founder of Facebook
Mark Zuckerber
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