Is there anything to worry about with the latest threat Heartbleed ?????

Unless you've modified the RG's firewall to allow it, there should not be public access through your Residential Gateway to any of the AT&T provided Cisco gear.  Thus there should not be any opportunity for a hacker to gain access to any of the Cisco gear in your home.  Assuming that they did gain access, and were able to exploit the deficiency, I can't think of anything they could really learn from the boxes except maybe what channel you're currently watching.

The exploit allows the attacker to read the contents of the system memory of the affected system.  What is in the system memory of your Cisco WAP or TV Reciever that you need to keep private?

Also, the TV receivers themselves (Cisco or Motorola) run Windows CE.  Microsoft provides an SSL implementation for Windows CE which is not based on OpenSSL, so the Receivers themselves should have no OpenSSL code in them anyway.

The "HeartBleed" vulnerability affects primarily Linux-based platforms, and a few BSD-based platforms (Apple computers are BSD, but not an afflicted flavor).

As previously mentioned, Windows products are not affected unless running packages like "cygnus," which allows Linux/unix apps to operate on a Windows platform, and then it must also be running specific versions of OpenSSL.

HeartBleed has been around for quite a while; it's only recently been picked up by the press and media.