It seems that it would be inevitable that people would compare the PRE with 3G S... my personal opinion is that Palm has been lackluster in the past few years. They have lacked the drive to produce something new. Compare the iPhone 3G and the previous Palms, it should give you an indicator of where the PRE would be. So its 3G S for me.
I think that iphones having a lot of apps would be better than a well-designed OS, not saying that the Web OS is well-designed. I don't have enough experience with it to make a judgment.
Well 3gs has some great features compared to palm's pre model but some things i like about palm pre is its pretty design and looks and its mutitasking feature with web's integration.