Another study has failed to detect XMRV in ME/CFS patients. I was pretty depressed about the news until I found out that, like the other follow-up studies, Kupperveld et al. used much broader patient criteria than the original Whittemore Peterson study. (Translation: their subjects may not actually have ME/CFS.) They also didn't use the WPI's more extensive testing methods.
You can read a more in-depth analysis from Stephen Ralph at Dancing with the Sandman.
So, no longer depressed. Just frustrated. Even if the WPI study appears more credible than the others thus far, we still need serious replication attempts by somebody other than WPI.
Anyone? Anyone? Bueller?