Let me start by saying I have only been on these boards a short time and have never participated in a TAA, so I think I am your target audience and this is just my two cents.
I think we need to look at this as we would a business owner trying to increase the sales of his or her product. The key is generating interest and excitement around the product in order to create the demand. If I look at VM's summary it looks like the average scores from the forumites is around 86-87. That is OK, but it's not anything that really gets me excited to participate. The two exceptions that had any real participation were the 2000 Chateau Faugeres St. Emilion @ 90pts for $38 and the 2001 Josef Leitz Riesling Rudesheimer Magdelenenkreuz Kabinett @ 90pts for $12.25. As far as the Chateau Faugeres, is concerned, it is apparently a nice wine, but at $38 I wouldn't call this a great QPR. The Josef Leitz, on the other hand, seems like a great QPR and makes me wish I had participated.
My point is that in a year of the TAA, the only time I really feel like I missed something was the Josef Leitz in February. If we are looking for mass appeal and want to generate participation, we need to establish a reputation for tasting high quality wines at good prices. Everyone is looking for the next great QPR and that should be our focus.
Beyond that, the host needs to "sell" and "market" the wine to generate enthusiasm. If a host doesn't have a wine that fits the bill he should pass to a host that does. If the host thinks he has a wine the forumites will love, let us know. Promise us we won't be disappointed and that participation will be worth our while!
Granted, everyone's palate is different and what I'm suggesting places a lot of responsibility on the host but I think it is necessary if you want to develop a following.
We can argue about rules, but in the end I don't really matter think they matter (although availability is clearly an issue). In my mind, the formula is simple... good/great wines with a good/great QPRs (and don't be afraid to call your shot!)… no more, no less. If we do that, I guarantee participation will increase.
Easier said than done, I know.