Has anyone played with this particular BLE module yet? I see all kinds of potential for the nRF51822 in the context of a Teensy 3.x(RF/++)/spi BLE module, as well as a stand-alone low power wireless sensor platform. It seems like it could take the place of the MINI54 and add some extra functionality beyond BLE and bootloader (ie. low power RTC, RF wake up/power on for the K20, other super low power wakeup/trigger events for the K20 etc. etc.)

It can't be much different than the RFduino module (cursory reads of the specs seem like it actually exposes more of the io). Anyway, beyond the bundled smartBasic platform, has anyone tried porting the Arduino environment to it (from my reads of the RFduino forums, it's not all happiness and joy over there right now - mostly because they aren't releasing the source for the bootloader and the shim between Arduino and Nordic's BLE softdevice blob.

Anyway, it seems like there is some good support/development going on in the sub-GHz band with the RF22B and in the 2.4GHz 802.11 space with the adafruit cc3300 breakout/module. I was wondering if this was a good candidate for BLE on Teensy 3.x platforms. It costs about $13 in single unit quantities, and the Laird dev kit for it is around $150 (a bit cheaper way to start playing around with the nRF51822 than Nordic semi's $400+ dev kit).