I've never been a fan of smart TV's. They never seem to be as smart as you want them to be, and if you do set up a home system with them, you are kinda stuck with that brand's "ecosystem". I have similar feelings toward TV's with integrated DVD players, but mostly because the players end up dying far sooner than the TV.
Yeah, from what I've read about the lack of Amazon; it's because of some licensing thing between WD and Amazon, possibly related to the fact that WD supports Blockbuster streaming service. All speculation, but probably not far from the truth. But to be fair, I haven't seen a single device that has everything in one; they all miss something or other. It's just a matter of choosing the device that supports what you want at that time. In my case, I primarily wanted an inexpensive device that would be able to access and natively play ISO files from a shared network resource - and the WD Live fit the bill and had Netflix as a bonus (although my BD player has Netflix already so that wouldn't have been a deal-breaker).
As far as TV's go, everyone says Plasma is better than LED/LCD. Better contrast, refresh, contrast, colors, saturation, etc. But the downside to plasma is the substantially higher power drain and the possibility of image burn-in (although that's better than it used to be). LED just refers to the backlighting technology (LCD uses CCFL backlight), but still uses LCD for the picture. I don't there is a
true full LED TV on the market yet (wonder why?). So, it just comes down to going to the store and finding the model that looks the best while having the inputs you need at the price you want to pay. Personally, I like BestBuy's Insignia line. They seem to have the best bang for the buck despite being a "house brand". Some people don't like them, but either I'm not as discerning, or they are just whiners.