Agree that the CVT has been around for donkeys years, with belt driven versions in rubbishy small cars in the 70's. The reason i brought up the Torotrak IVT is that although it is a type of CVT, it's different the previous versions. There's no real tourque limitations to the transmission like other CVT's and it also has a 'geared neutral,' so the transmission is constantly engaged, even when stationary. THis means there is no requirement for a clutch or tourque converter, increasing efficiency.
I don't necessarily see the fact that the engine doesn't change revs when accelerating hard as a 'problem,' a little disconcerting maybe, but it's just something to get used too. Bu this how performance is increased!