Be sure to check out the actual reseach papers linked in the article! I would have linked to them directly, but the article is full of follow-on links of considerable interest.
I'm quite partial to the idea that this was actually the whole point of the experiment, and they just spun it as "Let's see if we're in the Matrix!" to get more public attention (and easier grant monies).
If it is... I hope they do not crash the system with the test.
http://www.huffingtonpost.co.uk/2012/12/12/physicists-universe-simulation-test-university-of-washington-matrix_n_2282745.html
Be sure to check out the actual reseach papers linked in the article! I would have linked to them directly, but the article is full of follow-on links of considerable interest.