FLIF is encumbered by GPL which means it's not going to make it into any digital cameras.

The first official version of FLIF has not been released yet, and currently they are discussing releasing it under Apache 2 or MPL (Mozilla Public License).

Please Not MPL. Apache 2, so most company could understand, MPL they will have to spend a lot more time evaluating it.

And I dont know of any popular project that uses MPL apart from Mozilla Firefox.

We are probably going to change to Apache2 for the decoder, LGPLv3+ for the encoder.

LibreOffice?

Eigen (perhaps not "popular" unless you're interested in doing linear algebra with C++.. :-/ )?

Surely there are others as well..

If you want a weak copyleft license, IMHO MPL-2.0 is about the best available at the moment, and relatively easy to follow.

oh, good! :-)