We have had new rhythmic ac's come out in the past two years.  Austin got its "Jammin" back on 103.1 after a 4 year hiatus last year, Hot 96.9 in Boston came on at the beginning of this year, and Heartbeat 106.7 in Little Rock debuted to compete with longtime urban ac KOKY due to that station's DATED sound.  While places like Las Vegas, Phoenix, Fresno, Denver and Bakersfield have maintained rhythmic ac's for the longest time, other places like San Antonio and Albuquerque have lost theirs with no replacement.  In special cases, Sacramento's KHYL leans a bit urban, while KKBA in Corpus Christi is a rhythmic ac but it bills as simply an "AC."
Places that have never had one:
Tampa/St. Petersburg - urban ac WTMP bit the dust, but they can always use a rhythmic ac if an urban ac is not tried again here