Dark matter map reveals cosmic web
An international team of astronomers led by Nick Scoville from the California Institute of Technology have created a three dimensional map that provides the first direct look at the large-scale distribution of matter in the universe. This is best evidence yet that normal matter, like stars and galaxies, accumulate along the densest concentrations of invisible dark matter. The map extends to a time when the universe was only half its current size and shows that dark matter has grown increasingly clumpy, forming long flamentary structures. Observations with the Subaru telescope, led by Yoshiaki Taniguchi from Ehime University, contributed the 3D distanzce and time information. Details are in a paper by Richard Massey et al. in the journal Nature (January 7, 2007 edition).
More info: NASA web page