The OP has Time Warner Cable, not satellite.
And I can verify from personal experience that Comcast and Time Warner both have crappy HD signals.
Whether the issue is at the source or the problem of their installers is inconsequential. The end result is that most consumers get horrible looking HD feeds from standard cable connections. FIOS doesn't boast about the quality of their signal for no reason. Direct comparison screenshots show a remarkable difference:
The bigger point is that the LCD's don't inherently pixelate any worse than plasmas as per the OP's original concern. The problems is always with the source material.