i asked the same thing and have been told by everyone (including nitestick) that fsb/cpu clock speed is more important.
as far as seeing performance difference, that is. the only time you need to really worry about ram speed is if you do a lot of ram-intensive applications (i cant tell you what they would be).
as you overclock your cpu, the rams bandwidth will increase. but even at 267, you're still getting plenty of bandwidth for fast information transfer, from what i know.
"nagasama no longer drinks tecate, or streaks out of the night for anything, and he has a fine wife so he has no use for your girlfriend...she is safe..."