Google Art Project is a natural and necessary extension of art history education taking advantage of the digital metamedium. Since museums have had online collections, it has been an idea in the “adjacent possible” , just waiting for the right entity to put all those collections in the same place (figuratively speaking?). Google has done so in a way that emphasizes and pays respect to the context of a work (the museum where it came from) while allowing the free association of Bush’s Memex in the user-curation function. Is this the same as experiencing art in the physical world? Absolutely not. Is it an engaging and interactive way for visitors to build cultural capital? Absolutely. Is it a way to potentially expand our collective understanding of what constitutes art? Perhaps.
Just as a print of a painting isn’t a substitute for seeing the real thing, nor are digital reproductions – even in the gigapixels, though that is a very interesting feature of selected works in the Google collection. A digital reproduction on a screen (probably a screen of maybe 20 inches max, a smart phone in many cases) is never going to convey the aura Walter Benjamin attributes to authentic works of art. The most powerful art experiences I’ve had personally had everything to do with the physical experience of being with a work itself, appreciating scale, texture, and atmosphere. Google’s Project certainly is not that. Malraux’s words about the imaginary museum certainly apply: “Indeed reproduction (like the art of fiction, which subdues reality to the imagination) has created what might be called ‘fictitious’ arts, by systematically falsifying the scale of objects.” 
Thus far, Google’s Art Project strikes me as best described as a meta-museum. It is not an index of every work of art ever produced. It is curated. It takes objects from their physical context like a physical museum, following that same conceptual model which Malraux cited as the basis for his Imaginary Museum. This is nothing to be feared since “By the mere fact of its birth every great art modifies what arose before it”  In other words, a physical museum collects objects from different times, places, and imposes connections upon them. (Is this beaker more “authentic” in its case in the Museum of London than it is as a digital reproduction on your computer screen?)
Beyond its (tiny, two-dimensional) enormous scope, the Project’s interactive features may be what most distinguish it from its predecessors. Malraux said a function of reproductions is to allow us to “have far more great works available to refresh our memories than those which even the greatest museums could bring together” . Whether we look at the Project as a glimpse or fantasy of the physical possibilities to be visited, or a way to “refresh our memories,” it makes sense for us to have agency to peruse and organize as we see fit. Playing the role of curator in this wonderland of representation may offer a powerful opportunity for people to think critically about what they appreciate about a certain work of art (is it the brush strokes you noticed while zoomed into one of the gigapixel reproductions?) or about the art they notice in their surrounding environment.
In terms of Bourdieu’s cultural capital, the freeform nature of Google Art Project could potentially diminish its value as a teaching tool to facilitate upward mobility through cultural literacy. Based on Wikipedia’s summary, it sounds like the Project may have been better suited to this in its original form when it was Western-centric. However, the inclusion of a broader range of traditions including street art (which surprised me somehow even though it’s incredibly trendy now and I shouldn’t have been surprised) could also have a democratizing effect on people’s understanding of what art is, who can produce or appreciate it, and where it comes from.