I'd like to open up the discussion of "fixing" the yt coordinate
systems, as we move nearer and nearer on 3.0. Jeff, Nathan and
Britton have brought this up a couple times, that the x/y/z ordering
is not consistent with what they expect, and I'd like to figure out if
we can fix that now -- it's as good a time as any for bandaid ripping.
It may just be a matter of the transposition of buffers and the
x_dict and y_dict, or it might be more complex, although I suspect it
won't be much more than fixing those two items.