The personal weapon of most IDF soldiers is the M16, particularly, the M16A2, shortened CAR-15, M4, and M4A1 assault rifles. The majority of regular-service Infantry Corps soldiers are equipped with the shortened M16, but the longer model is still in use among recruits and reserve forces. In 2005, the IMI Tavor assault rifle was brought to operational use, and is intended to become the corps’ principal assault rifle in the future.
about the Tavor : http://en.wikipedia.org/wiki/IMI_Tavor_TAR-21
Right, however, the Tavor was neither needed nor requested by the IDF.