How will the authorities respond to the killing of a US agent and the wounding of another?
You'd expect them to come down hard on Los Zetas. But Los Zetas, right now, are not really in any state to be taken down. They're still pretty disorganized and independent, and not really all that powerful. A roundup like the one against La Familia back in late 2008 might work, and in any event would help stop Los Zetas from organizing and consolidating along the east coast and southern border, which is what they're trying to do right now.
The authorities already claim to have caught one of the shooters of ICE agent Jaime Zapata, in San Luis Potosi. I'm suspicious, of course, but it could well be that the guy received no protection from any of his Zeta crew on account of the severity of his crime.
Anyway, what to expect now? I think the authorities are going to go after El Lazca and El 40, the two old guard Zetas, and try to put a stop to the Zetas' attempts to organize nationwide. They'll get a little help from the Sinaloa/Gulf alliance, which to the best of my knowledge still holds.
What the authorities SHOULD do, however, is exactly the opposite. Leave Los Zetas for now and send in the big guns after Chapo and the big Sinaloa guys. They'll be expecting a crackdown on the Zetas, so why not give them a little surprise?
Interestingly, the military has been pretty quiet in Sinaloa in recent days. Perhaps the army is up to something? (Or of course, they could be just sitting around all day pulling up marijuana plants as usual.)