I got the JP version over the weekend, a friend flew it in for me. It was way smaller than I expected, the TV commercials show it as a slimmer version of the original, but it is actually way small. There's a ton of space in the box, which was about the same size as the box for the original PSX. They compacted the hell out of it, if it weren't for the need to be compatible with existing peripherals (controller and memory card ports) I think they could have made it even smaller.
The unit seems to be slightly louder than the original PS2 when the laser head accesses the DVD, but nowhere as bad as the original PSX or DC.
With the amount of cheap PS2 games out there, I think the $149 will start to pay for itself soon after a couple of good game purchases.