There's three Cubieboards:
The Cubieboard original (or Cubieboard 1) has the Allwinner A10.
The Cubieboard 2 has the Allwinner A20 (dual-core ARM7).
The Cubeboard 3, aka the CubieTruck, is also sporting an Allwinner A20. (I have this one)
I also have a cubietruck. I got it shortly before christmas and have been unable to compile a working kernel. Most annoying. It's running Debian Sid with the lubuntu kernel (3.4.61).
Otherwise it's an interesting little board. The 2GB of RAM and dual core processor make it quite capable. The simple "open" case is rather compact and includes screw holes to mount a 2.5" HDD/SSD. The SATA port is great for adding real storage, but being only a single port limits its usefulness as a server. A cluster of them could be interesting though.
The Dragonboard seems very cool. It is a pico-ITX board based on Snapdragon S4.
ARM quad-core Krait CPU, 2GB RAM, Gigabit Ethernet, Wi-Fi. Too bad USB 2, not USB 3.
Its the same stuff powering the Nexus 4 phone.
Too bad its only available with Android support, they are working on Linux support.
Uh, the Wandboard Quad model has three GPUs? What?