I'd say cpu speed, memory size, and HD I/O matter most now, but of course vid card matters too after it's all loaded.
CPU is important for decompressing and launching the game, but as soon as that happens it loads into memory, and swap if there is not enough memory. Bandwidth won't matter much, because 200MHz and 230MHz won't ever be your bottleneck, it'll be your hard drive that lags the load times.
If you run a psycho-speedy SCSI or SATA drive as boot and game install drive, with a slower drive for data, your game will load insanely fast because the drive will throw the data out to the memory FAST, and that is what changes your load time. The memory just holds it while the CPU decompresses and interprets, so FSB, while important, won't be visible really. I can see no difference between 2100MHz and 2450MHz in game loading, because my drive is what lags the system.
After load times, if you want performance in-game, of course video cards are important. Memory and CPU won't matter much here, unless they are grossly outdated compared to the video card.