When is the next Firestorm release? According to Ed Merryman: when it is ready.
The next Firestorm release is waiting on Linden code for the new Inventory API’s. These are changes that improve inventory loading speed and reliability. They are changes that are targeted at fixing the last of the avatar bake fail problems.
Fitted
If you use Firestorm, or any Second Life capable viewer not yet updated for Fitted Mesh (meaning most viewers), and come across someone wearing Fitted Mesh, depending on how it was made, you may see parts of the item stretching off toward the southwest corner of the region.

It is thought there is a fix for the problem prior to the roll out of Fitted Mesh. The problem is caused because the avatar used by Fitted Mesh viewers is different than for non-Fitted Mesh viewers. There are additional bones in the skeleton. If your viewer doesn’t know about those bones, it does not know what to do with clothes that use the new bones. The result is vertices in the clothes are moved toward the 0,0,0 coordinate of the region (the southwest corner).
