You also miss out on the Signature Edition content, which includes four extra items, an in-game armoury and the game's soundtrack.
He meant that the Black Emporium is equivalent to DA:O's Stone Prisoner, in that they both come with the game from the start; however, as far as I can recall you were actually able to download the Stone Prisoner content via PSN/XBLM.
Now that EA is pushing this whole "buy the game brand new or else!" thing, as seen with their sports games (Online Pass) and Mass Effect 2 (exclusive content), they've added the Black Emporium et al as a sort of inticement to buy the game new, lest you miss out on some cool content. It won't be available to download.
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