I’d like this feature for one reason: Rebirth has the best emulated 303 sound out there, and it’s free. Unfortunately, it can only be used as a softsynth in another app through rewire 
yup would be cool. But if the play / stop only work from the renoise then that would get quite irritating in the long run. What do you others think? Would you or could you others make music in a way that if you changed the positioning of notes - each time after and before each edit you’d be willing to switch the window? Or recording the notes… 1. go to renoise press play → 2. go to host press rec- > 3. go to renoise press stop → 4. go to host check whats recorded → go to renoise press play → go to host… and so on… ? I must admit that I really couldn’t.
Every step and edit would require 4 operations. That is 2 changes of view + the 2 presses you’d make in the renoise’s transport…
It would be great though if it worked like it should…
I thought this was a system freely available to implement for anyone? Sad to hear that the propellerheads have limited it so that the transport would not work from the other rewired software 
As a long time Reason user and lover, for me ReWire would certainly pwn!
To say the truth, it’s the only feature i am waiting for in renoise.
At the moment, when i want to start to do a song, I have to decide, which way to go, Renoise OR Reason. It would be awesome to be able to ReWire those two pieces of excellent software.
so… pretty please with sugar on top? 
EDIT: oh yes… and i have to second what Transcender said. Talking about the lack of demand, you shouldn’t look at the current user base (well… except for me and some others… haha). You should think about how many potential users didn’t join us, because there isn’t a support for ReWire. If those are many (what I think they are), there’s definatly a huge demand. It’s just difficult to estimate.