[asa] Cosmologists questioning the Copernican principle?

I was quite surprised to see the following New Scientist article:

http://www.newscientist.com/article/mg20026821.200-is-earth-at-the-heart-of-a-giant-cosmic-void.html?full=true

The gist of the argument is as follows. Dark energy has been proposed
as an explanation of the apparent accelerating expansion of the
universe (as illustrated by distant type 1A supernovae being fainter
than expected). However (as I understand it from the article) the
theoretical predictions of the quantity of Dark energy are out by 120
orders of magnitude, implying an incredible degree of fine tuning.

The alternative (for which the article describes potential experiments
to test the theory) is to propose that the earth is in the centre of
an enormous cosmological "void" ( comparatively sparsely populated
region of space) surrounded by denser material. It should be noted
that this "void" contains most of the observable universe! This would
violate the Copernican principle of the earth being in no special
place in the cosmos, but would exhibit isotropy ( universe appears the
same in all directions - uniformity of the Cosmic Microwave Background
Radiation), while requiring the earth to be near the centre (thus
violating the homogeneity assumption - the structure of the universe
varies with distance from the centre). One quote from the article
seems to sum it up well; we live in a very improbable universe, and
the new proposal trades one improbability (Dark Energy) for another
(Earth near the centre).

I would have thought that Young Earth Creationists would be very
excited about this. However, I emailed a former colleague who is a
YEC & he was less than excited; the article had been passed round
creationist circles, but there was not much comment. He felt that the
New Scientist article, as always, was too hyped up. (However, there
are also positive discussions of it on the Richard Dawkins website as
well).

I'm not a cosmologist, but it appears to me that to invoke some
mysterious form of energy, the nature of which we don't know, and
state that it comprises around three-quarters of the material in the
universe, in order to explain some observations that don't fit with
the standard model seems a little like a desperate fix and just shows
how little we really know. Perhaps some cosmologists on the list can
explain if there is other, independent evidence for the existence of
dark energy. Otherwise to invoke something we know nothing about to
explain observations we can't otherwise explain seems about on a par
with the Intelligent Design argument (which I think is a cop-out).

What do others think? I know the New Scientist is given to hype. Is
this just another case of it?

Iain

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