I want to try these too. This thing of liquid pads, allows to presage that a new evolved generation of headphones is coming soon. I hope in sound technology too.
It should be a logical consequence the coming of t80 and t90 but not so granted. This could be a commercial experiment, so that if people start to buy t70 instead of dt770, they could replace the entire line. Or maybe they are just creating a middle level between the dt line and the top of line. T5p occupies another price range. I doubt that t70 will replace the T5p.
If they are improving the dt770 with this t70 I don't see why they shouldn't improve a model like dt990 with his so debated trebles which affected the full enjoyment for a lot of buyers. The dt880s are already good ok, but everything can be improved.