I replaced mine about three years ago. The old one was heavy and in the process I damaged my left rotator cuff tendon. It finally gave way last year and had to be surgically repaired.
If you do it yourself it might be a good idea to get help.
I paneled the area behind the old TV and mounted the new one on an articulated arm so it can be rotated out for access to the storage area now available.
Of course with a new high def TV I needed to get a SK3005 Traveler automatic dish that gets the HD satellites.
The good news is that Direct TV gave me free HD for two years and after two years were up made the free HD deal permanent.