It is so new that its formal specification is not even completed yet.

The initiative's website is here: http://tiff-a.org/.
Their purpose is to define an official spec for TIFFs which are guaranteed to "survive" long-term archivation.
So this request is not an urgent one yet -- see this post as a placeholder to keep the topic on the radar.
The TIFF/A Initiative are also looking for experts who are supporting their work. Have a look at their website!