On Facebook, Aubrey de Grey said:
Stari is right. Spectacularly oversold. The mice are broken in one very well-understood way (no telomerase, so eventually over-short telomeres), and they have been constructed so that that problem can be fixed with a drug, and lo, lots of the downstream consequences of the problem are also fixed. Duh.
Michael: the cancer issue is not really relevant here, no, because mice have lots of telomerase normally and don't use telomerase thrift as an anti-cancer tactic.
Prior to that, I had said:
I'm surprised this happened so soon. Nothing like this has been achieved before. The lack of increased cancer risk is the key point.
Again, even if this is fixing something deliberately broken, I wasn't aware of rejuvenation like this being achieved before. I must admit that in this field I generally just follow the popular science material and don't delve too much into the literature, though. The only blog I really read that goes into the science is Fight Aging. Still, I'm waiting to hear of a prior example of rejuvenation on this scale being demonstrated as a proof of concept.