The article is confused about ARM chips, which are practically never socketed. It wouldn't make any sense because ARM CPUs are highly integrated---they tend to include on-chip equivalent of North Bridge, South Bridge and many peripherals such as video hardware, USB, Ethernet, I2C, serial and parallel I/O ports, timers, counters etc.
In fact, that's the main problem with Intel in the embedded and enthusiast market: it's hard to make a small/low cost platform like Raspberry Pi because you need an expensive CPU... _and_ the chipset and peripheral chips. The cost difference is staggering---there are ARM microcontrollers that cost less than a dollar (admittedly, not the ones that you can run Linux on, due to lack of virtual memory, and small flash/RAM).