I'm posting this here too, since my druid is what made me consider this, and since druids are most likely the ones to get the most use out of these. Anyway, past here I'm just copy/pasting my general forums post.
So, as a druid, I'm coming to realize the fact that I need to be ready to respec when needed between feral and resto. Since I realized that, I've been annoyed with the idea of having to redo all my talents everytime I want to change modes. So, I am looking at addons that manage talent builds, and was wondering if anyone here has experience with them. There are two main ones I've been looking at, but I am fully open to suggestions if there are others people use. Linked below are the two I am looking at.
Talent Planner - http://www.wowinterface.com/downloads/info6503-TalentPlanner.html
Talented - http://wow.curse.com/downloads/wow-addons/details/talented.aspx
On a side note for talented, it requires a data addon to work properly apparently, which I will link for the convenience of those interested in trying it.
Talented_data - http://wow.curse.com/downloads/wow-addons/details/talented_data.aspx