As someone who has had ME/CFS for 25 years, I commented extensively on my blog about XMRV, advising caution while much of the ME community was grabbing XMRV with both hands and running with it.
That was never justified.
I did not believe, based on the then available evidence, that XMRV, in relation to ME/CFS, was indicative of anything very much, except as another line of enquiry that needed to be followed.
I simply hadn’t sufficient faith in XMRV to get my hopes up. And nor should anyone else who was actually paying attention at the time, instead of investing XMRV with a significance and an excess of optimism it did not warrant. Even the original researchers recommended caution – and were mostly ignored.
I understand the craving for answers, which are mostly lacking when it comes to ME, but that should not cause us to abandon our critical faculties.
This new research, like the original, used a test population (186 in this case), far too small to yield statistically significant results, so there is still scope, as I said originally, for more extensive research.