From the FCE4 specs:
• A Mac computer with a 1.25GHz or faster PowerPC G4, PowerPC G5, Intel Core Duo, Intel Core Duo 2, or Intel Xeon processor. For AVCHD: A Mac computer with an Intel processor
So it'll run, but if you're source video is AVCHD (I note you posted on the HF100 on another thread) you won't be able to use the log & transfer tool to pull in your AVCHD clips, as this feature is supported on Intel Macs only. You'll have to resort to using a third-party app for conversion to AIC: Voltaic, for instance (which takes 12x whatever the length of your clip is, on average, to run the conversion).
Andrew.