(copy from reddit, so that more developers see it)
According to our wiki https://github.com/ethereum/go-ethereum/wiki/Frontier
License is LGPL. It is a bad idea, for proprietary vendors will not be able to include this software into their systems. It must be non-copyleft. I.e. under MIT/X11 license.
A small example: TCP/IP sockets library came from BSD UNIX into both Linux and Windows as WinSock. Do you think Microsoft would be able to include this if it were LGPL? Not a chance! MS would have to develop TCP/IP implementation from scratch, which would result in harder-to-write cross-platform applications, hurting Open-Source developers mostly.
Same for Google WebM / VP8 video codec and Ogg Vorbis audio free software codecs. Those are not protected by copyleft license, for a reason. It allows proprietary vendors to integrate open-source code directly, without thinking too much.
Copyleft license (LGPL/GPL) is only good, if you want to prevent commercial proprietary forks from taking over, if you do not have a better protection in place.
A fundamental software, like Ethereum, which I view as an operating system for Internet 3.0, should not be protected by copyleft, should allow proprietary vendors to integrate freely (into Windows and Mac OS X and Android). Ethereum is protected by the community consensus instead, from dumb forking, so copyleft license is not needed, and is harmful for this project.
Recommendation: MIT/X11 license.
-Technologov, an early Ethereum IPO investor and open-source community member.