Sprint and Clearwire announced today that they have flipped the switch on WiMAX in Washington D.C. and Kansas City and that they also strengthened Baltimore's 4G network as well. The Washington D.C. portion seems to be a fairly vast blanketing, reaching approximately one million people. The WiMAX coverage in Baltimore now covers around 725 square miles, or around 1.7 million people. To celebrate the new 4G networks, Clearwire is offering new customers of its Clear service a $50 service credit as well as plan pricing as low as $15 per month for the first two months of service. Sprint and Clearwire seem to be doing a good job of spreading the WiMAX goodness, especially ahead of the release of the HTC EVO 4G. Are any of you in the newly lit up areas? Are you planning on taking advantage of the new service by buying a data card or EVO? Tell us in the comments!