At the moment the lineup is PSP 3000 $300 (With a game)
PSP Go! $450
PS3 - $500
Just to argue your point, and many peoples issue with the price of the PSPGo!. The PSPGo! has a 16GB internal memory, also you are getting a Free game with the PSPGo! if you purchase within the first 10 days.
So
PSP3000 - 300 AU with Free Game
PSPGo! - 450 AU with Free Game
To get the PSP3000 up to spec with the PSPGo!, you would have to add a 16GB Memory Stick to the PSP3000. A 16GB Sony Memory Stick in Australia Retails for 190.00 AUD, which would make a PSP3000 @ 16GB more expensive than the PSPGo!. You could also argue that the PSPGo! having built in Flash memory would still outperform the PSP3000 due to the speed of the memory compared to a standard memory stick. And yes you can purchase higher speed memory sticks for additional dollars.
Add that to the PAL promotion, which nets you 3 Free games, you are effectively getting about 150.00 AUD (RRP) worth of games when you pick up your PSPGo!. For example, if you purchase within the first 10days of PSPGo! release in the PAL region, you will pick up a copy of Gran Turismo PSP, + 3 other Platinum games, or GT for PSP +2 other Platinum games + Resistance Retribution.
I know you can pick holes in that argument, and not everyone wants 16GB's of storage space, some people just want to play games on their PSP and like physical media. The PSPGo! isn't for everybody, I'm just trying to even the field a bit and show that the PSPGo! isn't as 'horribly overpriced' as many people are making it out to be.