It's a strange architecture. Most modern machines are symmetric-multiprocessor (SMP). That means programming is very straightforward - all the processors share the same memory space and each processor can do any work you like, so you just have to worry about the normal threading issues (race conditions, deadlocks, etc.) but it's otherwise just standard multithreaded programming.</p><p>The PS3 is not SMP - it has one main processor with 256MB of non-video RAM (a big chunk of which is reserved for the OS) and a lot of smaller coprocessors that have very limited RAM (256K). If you can fit chunks of work nicely into 256K, then the thing screams. If you cannot, then you have to do most of the work on the main processor, in less memory than is available on the Xbox360. In other words, you've gone from 6 hardware threads on the Xbox to 2 on the PS3. The combination of less general-purpose processing power and less usable main memory is a really hard problem to solve.</p><p>Now, for a lot of games, the Cell is great. Fighting games, puzzle games, art games, ARPGs, JRPGs, platformers. Any time you can offload individual character animation or rendering to the SPEs, you win. The PS3 can animate and render a whole lot more mobs in a scene than the Xbox360 can. If you have a physics calculation like waves on water or swarm movement that is easily separatable into small chunks, the PS3 is also superior.</p><p>But think about an open-world game - especially one with the sort of wide-open spaces and anyone-can-go-anywhere gameplay of Skyrim. We did open-world games and we constantly had trouble because physics and AI could interact over a long distance. We broke the world up into cells and aggressively limited the range of some computations to avoid this problem, but still, a lot had to run on the main processor because once the size of a physics calculation or a pathfind exceeded 256K, you couldn't do it on the SPEs. And believe me, pathfinding data alone in an open-world game is always going to be larger than 256K! AI in modern games is expensive, and we know that Bethesda takes their AI very seriously.</p><p>Maintaining a large, persistent world also means keeping track of lots of stuff, and that means memory. On the PC, you have practically unlimited swap and tons of main RAM, so it's not an issue. On consoles you have limited RAM and swap space and fragmentation can kill you if you dead. To be honest, I'm surprised the game runs as well as it does on the Xbox360, but again, you have more memory there and they have the ability to "steal" RAM from graphics if they need it, whereas you can't on the PS3.</p><p>So while I wish Bethesda had overcome the technical hurdles and made the game workable on the PS3, I can hardly fault them for coming up short. It's just not a platform well-suited to the type of game Skyrim is.