I did a quick search and didn’t find any threads about it.
It’s a really fun program, and easy to use. I made a little dumb VSTi, if you’d like to check it out:
It’s only got volume, decay, and one modulation knob (which you can adjust with your midi controller mod wheel too), but I plan on continuing development. 
www.synthedit.com - for us non-programmers out there!
I hate it. I am used to reaktor and the GUI and “look and feel” of synthedit sucks compared to that … maybe If I feel really masochistic and have a whole week off I will try to do something with it. 
Really? I found it very user friendly. But I guess it’s all what you learn on.
I’ve never used Reaktor, and at about $350, you can’t beat synthedit’s cost too (free, $20 to register I think).
I tried it some months ago.
The idea of saving as VSTi is great, but at the moment, it lacks of a lot of basic elements Reaktor has (logic ports and math stuff mainly).
Too bad Reaktor is really slo-o-oow when used in ReNoise.