Had anyone heard the names for these expansions before this announcement was made?
I know Dark Ages hadn't been announced and thought Guilds hadn't been.
I can tell you two more things.
The base cards in that product have art, full-card art. Copper with art, etc. So, while you can buy it to replace worn cards, or in order to play the game without having the main set or Intrigue, or to play with 5-6 without having both the main set and Intrigue, you can also get it if you are one of those people who thought the base cards should have art.
Dark Ages is 500 cards but is not a standalone. So while you are only getting one expansion this year, it's a big one.