Now this thread seems to be getting on a more even keel, I'll come out from lurking & post...
I joined TACCA because it promised to do more in the way of promoting to the general public than NCCA (of which we are members, too). Since joining, the biggest benefit has been the meet-ups, and I'm really looking forward to the one in March - I reckon we learnt more really useful stuff there than in all the other training days I've been to, and we were able to give the benefit of our own experience (we have been doing it since 1993).
I share a little reservation about the structure of the organisation, and I don't think Andrew's posts, originally at least, were outrageous, but we'll see how it works out - one day it will probably have to change. In the meantime, we're benefiting from the meet-ups, there's some hope that it will promote good standards in the business, and communicate with potential customers, so we're sticking with it.