It does seem like the interest in waning on these sets, but I'm still looking forward to them for two reasons.
I don't know if it's interest so much as excitement that is waning. At first we were all blown away that we were even getting TNG in HD, but now that the excitement has worn off and we are just patiently waiting for the sets to be released. At least that's how I feel.
Interest isn't waning. When everything is A-OK, what is there really to talk about? We are all used to the amazing upgrade, so now it's a matter of expectation rather than being surprised by the sampler and season 1.
Look at the five threads. Which has the most activity? It's season 2, because it was a trainwreck. I would consider it a bad sign if there was extra forum attention to the remaining seasons.