There is an interesting article Ultracold Bose gases deviate from the textbook picture in the Search and Discovery section of the July 2011 Physics Today. [My issue just arrived by snail mail today!].
It discusses how recent experiments have quantified deviations from the non-interacting boson theory of Einstein, which is taught to undergraduates.
It seems that these deviations can be described by Hartree-Fock theory. One might argue Hartree-Fock is also rather "text book".
For all the hype, somehow I cannot get excited about atomic BECs. To me, there seems a distinct contrast to solid state systems such as strongly correlated electron materials which exhibit properties (high-Tc superconductivity, spin liquids, heavy fermions, pseudogap, non-Fermi liquid metals,...) which are such a long way from anything remotely "text book"-ish and whose explanation requires the development of new physical concepts, approximation schemes, and numerical methods.
But, perhaps I am missing something.
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I agree with you that the explanation of most experimental BEC phenomena requires no fundamentally new physical concepts beyond what was already known in the 50s and 60s for hard-sphere gases. (Degenerate Fermi gases are qualitatively new, but that's a different story.) However, new theoretical techniques and approximation schemes are in fact needed--and have been developed--to fully describe these gases. As one prominent example, consider the herculean efforts to calculate the (manifestly non-perturbative) shift in the superfluid transition temperature due to interactions. The textbook treatments, e.g., Fetter and Walecka, are just wrong, as shown in experiments and by more recent theory.
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