The big attraction of the ISS is laboratory where gravity can 'removed,' which can be useful for understanding processes on Earth. This is valuable to some companies. Right now a couple companies are currently running experiments on the ISS.[0]
Proctor and Gamble wants to better understand why colloids(shampoo, liquid detergents, medicine) separate, because that affects the shelf life of their products. If they can turn off gravity, they can figure out what other processes cause colloids to separate besides just gravity.
As far as manufacturing goes, there are not many products that are worth making in space right now. You need a product that is more valuable per unit mass than the cost per unit mass to launch something to LEO.
Now the interesting thing is that there have been commercial products manufactured in space. Latex microspheres were produced on the space shuttle and sold as calibration sources for microscopes.[1] Because microscope calibration needs literally microscopic amounts of these microsphere, per unit mass the product was very valuable.
[0] http://www.nasa.gov/mission_pages/station/research/news/comm...
[1]http://www.panix.com/~kingdon/space/manuf.html
[1]http://www.panix.com/~kingdon/space/manuf.html