Professional anything is likely impractical on PS3. That's not it's target though. For home video editing it should work okay, limited only by the speed of the HDD. For the record I've video edited on a P133 with 128 MBs back in the day!
But I'm willing to bet this experience was not a pleasant one. Sony will obviously want whatever functions the ps3 will perform to be a "pleasant" experience and not a PITA.
Sony will obviously want whatever functions the ps3 will perform to be a "pleasant" experience and not a PITA.