Not many users of Arduino on the Core2 - yet...
It looks to me like a lot of functionality must be developed for the Core2. As the firmware is being improved from earlier versions, I'm experiencing a lot of odd problems in UIFlow online and desktop, with connectivity, response to touch input, failure to execute subroutines, etc., which seem to be improving with each new release.
I expect the Arduino libraries to improve over time as well, but until these are known to be functionally complete, I am avoiding the Arduino RAD environment, mainly because it is not designed for (WYSIWYG) graphics.