QUOTE(Peter @ Jan 16 2008, 13:14)

The UI Element specification is not finished. If we released the new SDK now, people's components using it would most likely need constant updating to keep up with newly added functionality. There's no estimate on when the SDK with UI Element specification included will be out.
Other than that, I'm disappointed with quality of most of third party panels for Columns UI (no disrespect towards musicmusic or his work intended). I'm prioritizing development of my own UI Elements over allowing third parties to make their own, so most people can get what they want out-of-the-box without installing dozens of third-party DLLs.
Can you give a few insight to prepare existing panels code to the future UI Element APIs ?
I suppose externalizing the window creation code is the first step ?