That made me a bit sad since there are some pretty annoying bugs in the pre-B silicon. One issue is Errata 019 where the buck power converter can malfunction in deep sleep mode causing a brown out reset. The workaround is to never let the part go into deep sleep. This is accomplished in the HAL software library by turning on the PDM peripheral. It is the peripheral that uses the least power, but having it turned on prevents buck converter bug from manifesting itself. The downside is that instead of the advertised 2 uA deep sleep, the best that a real system can do will apparently require 20-30 uA, or an order of magnitude worse.
So a question for the Sparkfun people: Assuming that B0 silicon is actually available, when do you plan on using more recent silicon on your modules? What will the process be for upgrading your modules? Will there be an announcement or a part number change?