It looks as though only the Extended version has Adobe LiveCycle Designer ES. In other words, it seems to me that only with the Extended version could I create fillable forms which require the end-user to have no form-filler product.
The ability to add digital signatures is nice, and it might come in handy - not immediately, only potentially, and at the moment it's not essential.
The ability to include Flash video sounds nice, and I'll probably find a use for it.
Thanks for the link, Smee!
As for Yib, it sounds as though you've been totally... what's the word? ... zonked.