What is the cost saving from manufacturing bikes in China vs USA or Taiwan? I went to a bike shop recently and was surprised to see big "Made in China" stamps on the Trek mountain bikes. I did some research and apparently all the big bike makers manufacture in China now. I seem to recall a decade ago the frames were made in America or Taiwan and the high quality Shimano running gear was made in Japan. 

The question I have is how much do manufacturers save by building frames and other components in China vs America and/or Taiwan?
I think my rough estimate would be 10 to 15%, although an argument might be made for less taking into account markup.  Cannondale was one of the last big manufacturers to produce all their frames in the US.  We carried them in a shop I worked at during the time they transitioned over.  Basically, one year all their bikes were ten to fifteen percent more expensive than their comparable counterparts (Trek, Specialized and Kona at the time in this particular shop) as it had been since I worked there.  The next year the prices were more in line with the other manufacturers and the frames had "Made in China" stickers.  

I have checked in the last few years, but some manufacturers used to still build their highest end products in their home country.  Beyond the big manufacturers there are still many smaller or custom builders active and alive in the US.  If you look at the pricing differences between a litespeed, seven or lynskey and a major manufacturer, you may get an idea.  But you may also choose simply pay that higher price and get a bicycle that was for sure designed and made here in the US.