Rockstar just put out a fan-submitted Q&A regarding GTAV, which can be found here.
There’s some questions about customizable weaponry, maps, multiplayer, etc. But the two key points of information that I was most curious about are:
(1)…In order to provide the best possible experience for such a massive and detailed world, the game will have installation requirements on both Xbox 360 and PlayStation®3 systems. For Xbox 360, Grand Theft Auto V will ship on two discs; Disc 1 will be used for a one-time mandatory install and Disc 2 will be used to play the game. After the install, players will be able to enjoy both Grand Theft Auto V and Grand Theft Auto Online without any need to switch discs.This initial install will require an Xbox 360 Hard Drive or an external 16GB USB flash drive with at least 8 GB of free space. If using a USB flash drive it must be at least USB 2.0 with a minimum 15mb/s read speed and formatted for Xbox 360 use. A new USB flash drive is recommended to ensure optimum performance. For PlayStation®3, the game ships on one disc and will install content as soon as you insert the game. The install is roughly 8GB, and players will be able to play as soon as the install is complete.* * *(2) The only versions of the game that we have announced are for the Xbox 360 and PlayStation®3 which are set for a September 17th worldwide release. We don’t have anything to share about the possibility of a next-gen or a PC platform release at this time and we are completely focused on delivering the best possible experience for the consoles people have right now.
“Players can expect the same great gameplay experience on both the PlayStation 3 and Xbox 360 platforms as they have both been developed in tandem. Like all of our games, trust that we’re committed to making sure Grand Theft Auto V looks and runs as great as possible regardless of whether you pick it up for PlayStation 3 or Xbox 360, and we are excited for fans on both platforms to experience Grand Theft Auto V this September. We expect any visual differences to be completely negligible.”