Page 4 has the attendance by conference. Pac-12 is 4th with an average of just over 53k. That should go up, as the teams from pages 6 & 7 at the bottom (Colorado - 11th with 38.4k and Washington State - 12th with 29.7k) should be significantly improved in 2014 while the programs with the biggest upsides due to stadium size (UCLA - 92.5k and USC - 93.6k) were both about 20k below capacity in 2013 and have a lot of excitement around them for their 2014 seasons.
http://fs.ncaa.org/Docs/stats/football_records/Attendance/2013.pdf
http://fs.ncaa.org/Docs/stats/football_records/Attendance/2013.pdf