Sprint's Dan Hesse has just announced the first cities to benefit from the Now Network's new LTE service. Those will be Atlanta, Dallas, Houston, and San Antonio, all four receiving some legit 4G by the middle of 2012. The official tweet that revealed the 4G news also discloses that there'll be 3G network upgrades for those four markets, though no further details were disclosed. The odds are good that this has to do with Sprint's deployment of 1X Advanced (a more spectrally efficient form of CDMA) and the multi-mode cell sites the carrier is beginning to deploy that'll colocate its various network bands and technologies in unified locations. Needless to say, Texas is going to be a mighty fine place to have Sprint service in a few months' time.