Pistorious's legs were made by some company in Iceland. Now the market for long-sprinting double-amputee prosthetics is a very tiny one, but if more and more companies get on the boat with this one then we may see some really significant improvements in prosthetic technology and maybe even a really fast double-amputee--sort of a race to build a bionic man (it would be a good marketing decision to be the manufacturer of the world's fastest legs).
Of course they'll try to test these prosthetics to see if they provide an "advantage" but that's really impossible to determine. People already bring up the point that he'll never be burdened with lower-leg injuries--clearly an advantage. But it's also impossible to assess exactly how much energy is saved or wasted with the blades. Even the best science can't predict accurately what Pistorious would be running if he had legs. They tried to guess using vo2 readings as a proxy for energy expenditure--but that's far from perfect (they figured out that he uses less oxygen on straightaways than able-bodied athletes and thus had an advantage, but that decision was thrown out precisely because it was a pretty incomplete thing to base the ruling on, especially since they didn't test him on turns). It's simply not possible to tell if he'd be a 50-second quarter runner if he had two full-grown legs or a 42-second runner, which is why he shouldn't be allowed to compete.
It's a tragic consequence of his condition that he'd be denied entry into the Olympics, but it would be even worse than if they gave him a spot over an able-bodied athlete who had no unnatural physical enhancement. That being said I certainly appreciate Pistorious's determination to race in the Olympics and respect him for it: I would expect nothing less of a truly serious athlete to want to compete at the highest level.
A lot of people on here have commented dismissively that it "will make good tv to have him compete." They're damned right it will. This is incredible story about triumphing over adversity--and also good sense--but adversity nonetheless. Hate it or love it this is one of the most compelling stories to come out of track and field in a long time.