The best short form critique of this announcement I have seen is the post by theoretical physicist Matthew Buckley on the metafilter website:

Matt's comment.

After I read that comment I clicked through to his personal website and I found a nifty layman's explanation of the necessity for Dark Matter in current cosmo theoy:

Matt's web essay on dark matter.

If you don't have time to read his comment, what he says is that the results are not obviously bogus but they are so far-fetched that almost no physicists will find their daily work affected by the provisionally conceivable status of these results until a huge amount of double- triple- quadruple- and quintuple checking verifies them.