Well Wett seems to be doing only chips and K-04 as the hightest performing upgrade, and used to participate in the forum.
TAP, seems to have also now a stagnet product line other than appliying the same level of mods to new model cars.
GreedSpeed used to also post in the forum, but also do not take a active role in the forum.
There are a few reasons why some tuners have chosen not to participate in forum.
I still would like to see some participation, and also new products being refined and developed.

I would imagine that most tuners are busy working and don't have time to check out the site.
If you want more R&D and new products, then they need to be working and not hanging out on the internet, anyway.
Besides, the climate here is pretty mean at times and I would imagine they would rather be low profile.

Just pretty much more of the same old stuff. They have refined products, but not released anything new that would indicate that they had been too busy to monitor this forum.