These are to be expected, as 4K TV are also decrease in price, so 1080p TV for sure decrease pricing too.

There are report saying even many games on PS4 is not render at full 1080p for full 60 frame per second fluidity.
But this shouldn't worry much, as long as the 720p rendering quality is good.
I did compare this with some video that I download with 1080p and 720p based on Bluray source, and really I can't differentiate between the two alone if not display side by side.
Of course, 1080p will be the better one, but not night and day different, just very minor fine detail added, which you have to stand very close to the TV to notice.

Meaning is.... 1080p or 720p actually doesn't matter much, as long as the quality of the source is good.