Vassili starts talking about Splash:

To answer some of the questions I expect.

When will it be ready? For some definition of "ready", expect a preview in the release this fall. No promises as to the level of functionality of the preview--but much more than what you see above!

Yes, I will post it in the open repository. But, only when it gets to the point of actually being at least somewhat usable and useful. I don't want to spend time on publishing to two places until then.

It will not be a multiple-window setup like the current UIPainter.

Stay tuned to Vassili's blog for more information