The Iraqi military appears to have gained the upper hand in Tikrit even if it hasn't--as claimed--retaken the city.
Iraqi special forces spearheaded the attack by flying into a stadium to establish an airhead.
Iraqi troops with armored vehicles, other security forces, Shia volunteers, and local Sunni Arab gunmen who did not join ISIL converged on Tikrit along for axes of advance.
There is no word if non-special forces were flown in to support the initial air assault on the stadium.
Iraqi helicopters provided fire support.
I'm assuming we provided surveillance support.
It isn't clear how much actual fighting has taken place, although some clashes were reported.
Reports of mass graves from the so-far brief ISIL occupation are already coming out, as well as killings by retreating Iraqi forces. Wonderful.
See here and here.
UPDATE: The Iraqis landed troops north of Tikrit, too, which hopefully disrupts ISIL more and keeps them from holding the line at Tikrit.