I've never understood the hand-wringing over multi-disc games. The original Metal Gear Solid and Square Enix's Chrono Chross were each two disc affairs. Final Fantasy VII shipped on three. Final Fantasy's VIII and IX were four a piece. Even Mistwalker's Lost Odyssey, an Xbox 360 RPG released in early 2008, shipped on four DVDs. Heck, Mass Effect 2 which came out last week, uses two. Complainers? Not to speak of.
Latest case in point: GameFly's preliminary Final Fantasy XIII game description suggests Square Enix's forthcoming RPG opus will be "a three disc game" on the Xbox 360, as opposed to the single Blu-ray disc it'll ship on for PS3 owners.
Time to take a baseball bat to your Xbox 360, then pick up a PS3?
A couple things. First, Square Enix honchos were saying as much already last year. VG247 broke the story at GamesCom in August, quoting Final Fantasy XIII producer Yoshinori Kitase as saying "We're aiming for about three discs for the Xbox 360 version." A gazillion blogs picked that up, so GameFly's 'reveal' is only news if you don't already follow the daily tittle-tattle.
Second, who cares? Does disc-swapping impact your play experience? I've been tinkering with the Japanese import version of Final Fantasy XIII (PS3 only) and the game pauses all the time to load cutscenes or new areas, as all games do. Swapping discs a couple times adds a few extra stops to an already peripatetic process. That's it. You might as well grouse about the time it takes to power on your system each time you play.
Third, recall you can dump Xbox 360 discs to the hard drive to mitigate drive noise. While that may or may not mitigate the disc-swapping factor (it'll depend on Square Enix's security requirements) it'll almost certainly speed data access times, eliminating any bottlenecks levied by the DVD drive.
The PS3 version of Final Fantasy XIII installs nothing of consequence to the hard drive, so you're streaming data off the Blu-ray disc as you go. The PS3's Blu-ray drive moves data at roughly 9MB a second. Assuming average latency and seek time, a generic 5400RPM hard drive is still loads faster. If the game has any notable transfer bottlenecks and you're comparing an Xbox 360 hard drive install against data streaming off a PS3 Blu-ray disc, one guess which system's going to be faster.