Everybody knew something big was coming with ps2. Sure the realization of jaggies wasnt as evident as it was after ps2 released screens but that helped to add to the hype. Plus, We had been seeing small increases in bits system by system (8-16-32-64). Thats not even pointing out the fact that we had only seen one true 64 bit system which was only a cartrige based system (allowing the 32 bit ps to have graphics that could compete w/ n64).
So in all reality it really felt like a jump from 32 bit to 128 which was huge. PS2 just got a lot of attention because it was the follow up to the "great" ps1 etc. The whole 128 bit hype, was also followed by all kinds of rumors etc with the "dolphin" and xbox (with those sweet looking tech demos).
In this case, we are just moving from 128 to 256 (which hasnt even really been confirmed yet surprisingly). Sure its a big leap and it fuels some sort of hype, but almost skipping a generation like before just added so much to the pie that today we couldnt possibly match that hype.