I ordered two of these last Thursday from The PiHut (http://thepihut.com/) and they turned up this morning. I am impressed by the size and the immediate compatibility with my existing B+ project. I splashed out on a board only and the bundle with their essential kit.
For this test, I simply transferred the micro-SD card and USB WiFi adapter from a running B+. The micro USB to standard USB socket came with the kit.
The picture above shows a Raspberry Pi Zero fitted with DIL socket (also provided in the kit) on the GPIO pins so it can sit nicely in the T-Cobbler Plus. Note that the power is supplied via a power monitor that shows current with an active WiFi connection; standalone, running linux, no active apps, current consumption is around 0.08A.
The Zero is an interesting solution for IoT; board area is around 1/3 of the B+, then choose any kind of wireless networking; Bluetooth, WiFi and/or GSM. It runs the same Broadcom chip originally used on the A+, but at a faster clock speed. The GPIO pinout is identical to the B+.
The Raspberry Pi Zero costs £4 quantity 1 – great value!