In recent comment to a blog post, Sergey observed that the usage of the terms 3G and 4G is completely different in the US and Europe. While in the US, the term 4G is used instead of LTE, it's exactly the opposite in Europe, where the term 4G is not very prevalent and LTE is used in the mainstream press. Both parts of the world have reasons from a marketing point of view to do one thing or the other. And by the way, some even call UMTS networks 4G in the US. And to dazzle you even more, a well configured dual carrier UMTS network can easily compare with a 10 MHz LTE network, the prevalent bandwidth in the US, or even surpass. And to drive the point home, a 20 MHz LTE network in Europe easily beats a 10 MHz network in the US. There we go, the terms 3G, 4G are completely meaningless but unfortunately suggest that one thing is better than the other when even 4G can't be compared to another 4G network.
So perhaps we have to go back to the roots? Perhaps everything based on UMTS should be called UMTS and everything based on LTE should be called LTE, at least by engineers who know what they are talking about!? And if you really want to compare performance, the terms won't help much just like the terms 3G and 4G. But at least they don't have this bias in them intrinsically that suggests one is better than the other. Well, and if one really discusses performance, then one has to to pull out lots of parameters such as bandwidth used, modulation and coding schemes available, cell site density, backhaul capacity, etc., etc., irrespective of the technology used.