The RTM versions of the two authoring tools for SCOM 2012 are finally here:

• System Center 2012 Visio MP Designer—VMPD—is an add-in for Visio 2010 Premium that allows you to visually design a System Center Operations Manager Core Monitoring Management Pack. VMPD generates a Management Pack that is compliant to the MP Authoring Best Practices by simply dragging and dropping Visio shapes to describe your application architecture and configuring them through the Shape Properties. Download it here.
• System Center 2012 Visual Studio Authoring Extensions—VSAE—is an add-in for Visual Studio 2010 Professional provides Lifecycle Management Tools to support Management Pack Authoring. Download it here.