AIR 2 app vs Silverlight 4 out-of-browser app?

Anyone released any Silverlight 4.0 out-of-browser app yet? does it compare to AIR 2.0?

Question about Silverlight 4, it has some webview-like control where I can write HTML+CSS right? What rendering engine does it use? What ver of CSS does it support? IE? IE7?

Planning to learn either Adobe 开发者_开发技巧AIR or Silverlight, but have not decided on which.

Just read the MSDN's Hilo: Developing C++ Applications for Windows 7 and I just can't imagine myself writing any native Windows app. The language, framework and libraries are too complex and pathetic.

Comment?

Seesmic Desktop 2.0 is a good example of a Silverlight 4 application that runs out of browser.

See http://windowsteamblog.com/windows/b/windowsexperience/archive/2010/09/14/seesmic-releases-seesmic-desktop-2.aspx