Well, this year, I just put my dates in last week, out of curiosity. I've gotten 2 emails since then. Last year, I did it much earlier and got MANY - easily over 10 by the time my trip rolled around. Some were nonsense changes -- 5.0 to 5.1, but some, like a few in my email above were significant, and would have changed my plans completely had I been relying on them.
Anyway, regarding the TP email, I don't subscribe to TP and have never seen one of these emails. I'm curious, if you input your vacation dates, how many times would you expect to receive one of these email updates? Is it only once as your vacation draws near or could it be multiple times as they seem fit? If it's mulitiple times, that would be highly annoying to me.