While I too would rather have the campaigns scattered throughout each for variety, I can see why they'd do it this way as well. It allows them to go much more in depth with each campain. Not my preference, but I'm not making the game, and I know it'll be a good story regardless.

However, as I see it most of the negatives and blizz-hate I'm seeing here is directed at points that are false. I wish I could find the actual articles which state the following, but it's late and I don't care enough to look.

First, Blizzard has stated that each installment of the 'trilogy' will be a completely *stand alone* game. So if you only want the Protoss campaign, only buy the Protoss edition. You don't need the previous 2 to use it.

Second, Blizzard has stated that Battle.net will remain a free service. You will *not* have to pay to use battle.net. They're just exploring the option of adding a few additional features "above and beyond" that you could pay for, if you wanted.

And thirdly, the point of "do I have to buy all 3 to use all the unique units from each", well of course you do. But that's nothing different than how all expansions work - you had to buy Brood War to use the new units, but if you didn't care, then don't.
And don't mistake them, this is still 1 game with 2 expansions, they've just made it so you could get it in any order! It's the equivalent of only buying Brood War and still getting to play the game, just without a few extra units that having this hypothetical SC vanilla would give you. Multiplayer will work (for free) no matter which edition you buy, you just won't have access to a few unique units that each edition has.

I hope this has cleared up some confusion.