I don't get the point of cutting a DLC/Addon in two.
Faster development cycle for the first half, meaning they can keep the masses hooked before they forget about the game.
It is a good thing, because it means they have to add sellable "killer" features to both parts. As mindx2 mentioned, they were actually at some point referring to them as two separate expansions anyway.
Now Feargus is saying it's one expansion divided into two parts, which is good because it means I get both of them for my $20 expansion pledge.
I am sure you are going to get 1st expansion part for those $20, i give $20 for the first expansion too
It say "first"