Can anyone provide a modern source for the average college student IQ of 115?
Ok I finally found the official demographic norming data from the WAIS-IV on page 104 of this book: 

"WAIS-IV Clinical Use and Interpretation: Scientist-Practitioner Perspectives"

You can see a preview of this book at http://tinyurl.com/z3vr44e.

The answer to my question is: Some college:      102.28
                                College graduates: 110.77