If they release Injustice for PC after so willfully neglecting a PC version of MK9, I will rage with the fury of a thousand EX Hellfires.
The release date definitely makes sense though as it as a healthy amount of time after the console release in April 2013. Publishers always do this because they think the extra time ensures greater sales of the console version upfront, and less piracy on the PC as a result.
The truth is, pirates gonna pirate, just like haters gonna hate. One pirated copy does not equal one lost sale.
People also seem to conveniently forget that the Xbox version of the game (and PS3 to a far lesser degree) get posted on torrent and pirating sites with huge download numbers even before the PC version in many instances.
The netcode will be the same as the console version. I can't see them setting up dedicated servers for a fighting game, so it will be Peer to Peer protocol on PC, just like it is on consoles. In other words, unless they hammered down the netcode (which is entirely possible), expect online play to be just as piss poor as MK9's.
At the very least, we'll no longer have to worry about luggin around consoles & monitor setups for tourneys, as we should be able to get some laptop action going.