Yup, that's how they do their Black Friday sales. You gotta refresh throughout the day to find something good. They will show "upcoming" items for the next block, but the more popular items fly off in minutes, so you gotta be ready.
Same here. I've had my Sony Bravia 40 inch since 2008. It's one hell of a trooper, still going strong with extensive use. But I want a 50 inch so I'll be looking. 4k would be nice but I might wait another 4-5 years for that. I don't expect much 4k content until then.
That is a good deal. If you switch to ordering most of your goods to on-line it will pay for itself in a few months. There's also the streaming content and "free" eBooks. I paid something like $70 for mine and it paid for itself in a month (granted I bought a couch with Prime shipping, which saved me a good $20 right there).