Got it on the 360. Waiting on the PC version. I just bought a GTX 970 (mostly) for this game. I swear if it's poorly optimized, I'm going to flip some tables. And then cry.>>27>There's no way in hell they'd let you use one in online, though.
In regards to the PC version, I very much expect there to be two online modes: GTAO, as seen on consoles, and some other sort of thing that allows for people to host their own servers.
I drool thinking about something cool that could happen, like SA-MP for GTAV.