Just a quick note for those waiting to confirm that the RTL-SDR Blog V4 is now in stock at Amazon USA. We have linked both the dongle + antenna set, and dongle only listings below. For customers outside of the USA please check our international purchasing links at www.rtl-sdr.com/store.
With the demand being high, if you were waiting please order soon as the next shipment most likely won't be in until January. To learn more about the RTL-SDR Blog V4, please see our product release post.