Gardening was the first talent thing I tried. It seems really fun, I like the idea of doing something that helps make the world look nicer for everyone that isn't competitive really, but social.
I don't know how it will develop, but right now the talent progression seems a little rigid. Each talent you get a quest using that talent that gives tons of XP. You can't really deviate from the path though, until you get Botany you are really only making components for when you do get it, that don't have any real intrinsic value. Maybe when there is an auction house or store this will be more useful. Maybe one of the low level items in each tree could be "toy" type things you can make, that are sort of fun and related to the specialization you picked.
One problem I noticed, if you decide to skip a gardening talent before botany, the quest you get at botany will be very difficult, requiring you to have components you don't necessarily have the skills to make. Maybe all 4 of the sub talents should be a prerequisite for botany?
Anyway, super fun. I know I should try and test the other trees, but the concept behind gardening in this game might make me stay. :)