I liked the Imprudence Viewer. But, it is far too behind the times for me to use it. But, that may change.
There is an article on Hypergrid Business by Maria Korolov: Work Resumes on Imprudence Viewer. Maria has news I had yet to hear. Seems a team is taking on updating the old viewer.
They will be avoiding the Havok Code Licensing. Unless a grid is going to implement Havok Physics and add Pathfinding there is no purpose to having the code in an OpenSim viewer. Plus few people even know what the code does or how to use it in Second Life. So, there is little point to adding it.
However, mesh, media on a prim and other parts of the SL tech will be added to the viewer.
It seems they will retain the V1 user interface. For a V3 interface one can use the sister viewer Kokua.
I wish them the best and will be watching how they progress.