The general look of the new iPhone 3G S is quite similar to the iPhone released last summer. But there have been some important changes inside the new iPhone. The 3GS comes in 16- and 32-gigabyte varieties; the prior model is the one with 16GB chip.
The reason of cost increase lies in NAND flash memory price going up. It’s used to store music, video, and apps on the iPhone.
Apple is one of the world’s biggest consumers of NAND flash memory, and has been cooperating since 2005 with chipmakers like Samsung and Hynix, among others, though in the unit used for the teardown the flash supplier was Toshiba.
Some components of the new iPhone are cheaper alongside with the fact that they’ve been improved significantly. That can be attributed to multitouch display which was improved be adding an oleophobic coating which doesn’t attract fingerprints and cleans more easily.
Some components are missing from the iPhone 3GS completely. E.g. broadcom controller chip connected to the display.

