I have been wondering if it was finally time to buy an HDTV to replace the CRT low-res TV we currently have. I was watching PBS' Blue Planet a couple of nights ago, and I noticed a lot of pixellation in the video. This isn't the missing difference frames problem that you often see with MPEG, where losing a packet or two causes random patches of color; this is the problem where you get fairly consistent patterning, I believe caused by the receiver signalling to the sender that it needs to slow down data rates, and it does that by substituting a lower data rate stream which does fewer of the wavelet compression thingies that are how JPEG/MPEG and similar compression schemes work.
It suddenly occurred to me: might my data rate be too low to fully take advantage of 1080p HDTV. Theoretically, I am paying for a 5 Mbps downstream data rate, but we all know that this a nominal rate, and what you actually get is dependent on many things that are beyond the ISP's control. Sure, the broadcast digital signal would be sufficient, and we do have a BlueRay player as part of our current setup, but since the vast majority of what we watch is Netflix, might HDTV turn out to be a pretty minor gain when our Internet connection is only nominally 5 Mbps?