According to UBM TechInsights, when broken down into components and raw materials, the total value of the 3DS is $101 USD, which is around $15 more expensive than the DSi was reportedly made for.

The inflation on the final retail price is broken up between actual manufacturing and labour, product R&D, packaging, distribution and advertising, whereas retailers themselves are getting a very small slice of the cake. Thus can be expected of hardware sales, in an industry where software follow-up is the key profit area for video game providers. Nonetheless, Nintendo are assuredly making profit on every 3DS unit sold.

Both retailers and industry analysts seem to have no problem with the price, claiming that the machine and its capabilities are very good value for money given what they do at this age of technology, as opposed to the expense of other devices with 3D screens and their corresponding glasses. They warn that retailers who are willing to offer major discounts on the console before it is launched will downplay its value in the public eye, and may ultimately hurt the system in the long run.

More details here.