From BlenderWiki

Cycles Renderer as Default

Cycles became almost feature complete this year. I think it's time to make it the default renderer, physically based shading becomes the Standard in the Industry and with Cycles we have a powerful and versatile engine for artists. This is targeted for the Blender 2.73 release.

There are some things, which should be done before the switch though.

Import / Export

IO scripts (obj, fbx, collada...) can import and export materials from / to Blender internal. There is some basic support for the Cycles material system already, but it is very important to fix the gaps. When a User opens Blender and imports a third party format, he should at least get the basics.

Solution: Import / Export code for Cycles materials. How to extract the important bits (diffuse shader, image texture...) in a large node tree is a challenge, but maybe the next point will help with this.

Shader presets

Node systems are a powerful and intuitive system for material creation. However, it can be annoying to add several nodes just to get a basic material. It would be cool to have a small default shader, bundled with Blender, some kind of Ubershader. I imagine to bundle 2 shaders with Blender, likely as a Node Group.

• Standard Surface: Simple shader for Diffuse, Glossy, Transmission, SSS.
• Standard Volume: Simple volume shader for emission, scattering, and absorption.

Other open points

• Texpaint with Images Some open issue with Texture Paint cloning, according to kopias in IRC. He wrote this script as workaround.