You may notice some of the newer animations in Second Life are getting better. There is motion capture to thank for some measure of improvement. Another contributor to the improvement is Avastar, a for purchase add-on to Blender.
One of the other handy features of Avastar is the ability to handle rigging a mesh. So, clothes makers and those making other objects rigged to the avatar will find Avastar a handy tool. I think this video gives one a good example of what it can do.[youtube P81l1NP3yck]
The video is a promo to get Avastar owners to upgrade. I think it shows off some of the abilities of Avastar pretty well.
The add-on also takes advantage of the new Second Life ability to upload the file type .anim. Using the anim format allows more control over the animations. See JIRA STORM-1803 – Adding raw anim file upload support for more details.
If you open Build->Upload->Animation, you can check out the allowed file types. Both BVH and ANIM are now available.