Sometimes in blog setups categories and tags are not sufficient to navigate/link posts properly. One of the blogs, I host, is a multi-author project. It seemed important to tag posts with authors in order to allow listing one authors posts ... but then we could not use tags and tag-cloud for keywords anymore, which would have been helpful to have. [maybe there would have been another way doing it, but we did not see it?]

Don't know how to solve this problem in a professional way, but from a user/low level programming skilled person view, an additional - lets call it tag-2 - layer (and field and whatever it needs to link/list tag-2 posts) seemed to do the job in my imagination.

Would that be complicated to implement in the next release?

One could use such a thing not only in a multi-author environment, but also if one runs a multi-language blog, which is one of our next projects and where i already see the challenge to offer a user-choice for his/her specific language.

[ps: i have asked for such a solution earlier in the support forum, but was timewise not able to try implementing mgsolipa's suggestion - http://forums.b2evolution.net/need-additional-tag-system-for-a-third-crowd]