Any news? 
Not much to talk to about it as I guess you didn’t read any of the release info; you can’t make native apps/games but only limited extension to iPhone apps. Native app support comes 2015/2016
And so that requires no modifications from Unity?
Nothing to modify as Unity cant even support it.
Sorry but I am not sure what that means 
Well I’m not sure how iWatch relates to Unity or even gaming at this point 
I am afraid you have to use native code if you want to develop apps for it