I hate to go on and on about how much I love FIOS when I know not everyone can get it. AFAIK, they haven't started compressing their signal yet, or at least not nearly as much as the other guys. On a 60" 1080p set the signal looks fantastic.
*edit*
But on my folks' 60" set with DirecTV, yes, there is definitely compression.
It depends on what I watch for me to notice the compression. Watching the few shows I normally do, I don't notice any at all.
Could it be a difference in TV sets or maybe setups that is showing you the pixelation?