What is GPRS?
GPRS provides an always-on, packet based data service enabling wireless bandwidth roughly equivalent to a 28.8-56kpbs dial-up modem connection, depending upon location and network conditions.
Many GPRS enabled handsets will also include J2ME implementations. As such, they will be important targets for J2ME developers.
For an in depth look at GSM and GPRS technology, you might also read AnywhereYouGo's excellent "Introduction to GPRS".