I knew there was a reason I liked Nathan's rigging, it's awesome. My proof, Blender's new Rigify addon is made by Nathan and the Blender crew.
If you haven't been blending IK/FK or using Rigify, what are you waiting for?
The animation/action I made is to help weight painting and put the rig through its paces. It passes the elbow over the shoulder test, wrist twist test and backflip test I run all rigs through before using them in further in Blender and Unity down the road Not perfect weight painting, but close enough to get you going and see the advantage of the 2 bone wrist/elbow... if you've been struggling there. My GUIBone example suffered from this. On the way to solving it, found a link to Rigify and quickly dropped my last rig and started using Rigify.
Reasons to use Rigify.
1) Its Nathan Vegdahl handy work
2) Its built right in blender
3) Modifiable bone template that can adjust to a wide range of bided rigs or different shapes and sizes.
4) My favourite option: Snap IK to FK and Snap FK to IK. I'd been pondering this option for a while now. No more pondering. It's a great help in IK/FK blending.
5) 2 bone wrist/Elbow. Other bones use the2 bone method as well on DEF bones, but the wrist is where you will see the biggest benefit.
Caveats: If you hit the Generate button a second time for a bone adjustment you made, you will need to re-apply the bone groups.
Nathan Vegdahl - http://www.sintel.org/news/simple-biped-rig-in-blender-25/
Model by Samuel "arshlevon" Sharit - face by me http://wiki.polycount.com/BaseMesh and thanks to Blender 2.6x
See Jamie's crash course on Rigify here:
Contact info: https://paulbzpud.wixsite.com/portfolio enter your email address in the "subscribe" section to get in touch with me for any freelance or game dev projects.