Exactly what Fuzzmosis said. If this trend continues, you'll be able to play 8-10 games and then need to upgrade your hard-drive. What does this sound like? Oh yeah, A FREAKIN PC.
What's next, videocard upgrade required to play Killzone 2?
I personally don't play 8-10 games at a time. I might be in the middle of 2 or 3 in any given, but that's about it. So after beating DMC4, I would just delete it and install the next game. It's a bit of a pain if you've deleted the game and all of sudden just had an urge to play a bit of DMC4 and then had to deal with the 25min install. Otherwise, it's not that big of a deal, especially if the tradeoff is zero load times.
My Top 5:
Shadow of the Colossus, Metal Gear Solid 3, Shenmue, Skies of Arcadia, Chrono Trigger
My 2 nex-gen systems: PS3 and Wii
Prediction Aug '08: We see the PSP2 released fall '09. Graphically, it's basically the same as the current system. UMD drive ditched and replaced by 4-8gb on board flash memory. Other upgrades: 2nd analog nub, touchscreen, blutooth, motion sensor. Design: Flip-style or slider. Size: Think Iphone. Cost: $199. Will be profitable on day 1.