Fitted Mesh Blender/Avastar Update: For those using Avastar, Gaia just uploaded a beta version of Avastar that supports the new collision bones. It's in the test folder #905.
So, I finally got around to making a simple top to test. I was pretty painless getting used to the process of weighting to the cBones. Most importantly, it did work with the sliders in SL.
The sliders in Blender versus SL weren't a perfect match. But, it was close enough. I think you'll still need to make some special sizes for extremely maxed out sliders like "Belly" for example.