How long does it take to get your official FAA certificate in the mail?
The Airmen Certification page you linked to is the best place to get a quick status update - the little note at the top gets updated when they move into a new batch of certificates. You can also search for yourself in the airmen certification database: When your new certificate or rating shows up there your certificate is probably in the mail.

How long it takes to get your permanent certificate depends mainly on how many they have in the queue ahead of you - Mine took about 60 days, but I've heard as little as 30 and as long as 100+.
If you're getting close to the expiration of your temporary certificate you can request an extension either online or at your local FSDO (more details over on this answer)