The forces that brought La Hune down are, sadly and predictably, the same forces that destroyed Rizzoli, on 57th Street, or the old Books & Co., on Madison Avenue: the ruthless depredations of the Internet (Amazon is regarded warily in France, and pays a bookstore-protection tax, but it is there), alongside the transformation upward (or is it downward?) of the inner cores of big cities into tar pits for a mono-culture of luxury.
My bets are more on the latter than the former. Give a bookstore a good, non-predatory environment to thrive in, and it will thrive, Internet and Amazon notwithstanding. (Cases in point: The Strand, or McNally Jackson.) Take that environment away and replace it with one that's a playpen for the aliterate, and no prizes for guessing what you get back: a billion-dollar brain desert.
Call me prejudiced for valuing bookstores more than (yet another) Starbucks or (yet another) bank, but there are some things that you just can't set a real pricetag on. One of them is the intellectual life of a neighborhood, and without a reasonably public local nexus for such things, it blows to the four winds. A university campus is one way to have that, but it's often too costly to be universally appealing; a bookstore is a more modest incarnation of that same impulse. And given how NYU has been buying up most of downtown Manhattan as of late, I'm leaning more towards the bookstore as a democratic repository of higher learning.