Kudos to the AnandTech team for a comprehensive, objective look at the differences between x86 and Power in one of the many areas of processor performance.
The reason I like this report is that it supports my answer to the question of "How much performance benefit will <insert platform here> I get?" which always is "It depends..."
Application performance is governed by so many things -- core speed, number of threads per core, core architecture, memory bandwidth, caches sizes, cache miss impacts, numbers of caches, NUMA topology, I/O pipes, I/O technologies, adapter types, disk caching, storage types, media rates. Then, map the application characteristics onto these factors and try to "predict" a number. It's not easy to find "a number".
Thus, anyone who tells you simply "Platform <X> is 3 times faster than platform <Y>" is clearly in Sales or Marketing!!!