As to pages, I do have the 52-page version (I do a lot of travelling), but with GE for the USA and SES for Korea, I am finding I am using fewer pages with the only problem of needing pages are with countries which issue full-page visas (China, Thailand, Sri Lanka, etc.). For China, thank goodness, I just got the 10-year visa so I don't need one each year.
Does anyone know (or guess) what the fee for the enhanced U.S. passport will be?