Actually, youre omitting a fourth and fifth, and raising fsb too high as it now pertains to DT.
IPC, or general arch effects, is one which is harder to market on, but is most important , and of course, number of cores.
Since both the former and the latter effect freq, its this combination you should really be concerned with. To me,
IPC
Core count
Itll be how the overall arch is balanced as to how good the freq are. Larger multi cored di wont clock as high, while wider, shorter piped arch's hinders clocks as well.
Since both AMD, and Intel, now with their i7 arch use IMC, the front side bus has been pretty much eliminated as something seen as a top priority, tho speeds can be still argued, the BW is no longer a priority.
Cache plays a vital role in apps, some more than others, especially in gaming, where more has greater effect, but on some apps, it matters little. Itll be interesting with W7, and DX11, and how it turns the needs of games over to cpus, while also, freeing up cpus, and having the gpus do more, how those changes effect gaming and perf overall, and the needs/rankings of cpus.
For each app, these (freq,cache,fsb) changes in order of effectiveness, and to pin down a certain order of relevance depends on said app