From the Study:

• 83% of college students and parents strongly agreed that higher education is an investment in the future, college is needed now more than ever (70%), and the path to earning more money (69%).
• Drawing from savings, income and loans, students paid 30% of the total bill, up from 24% four years ago, while parents covered 37% of the bill, down from 45% four years ago.
• The percentage of families who eliminated college choices because of cost rose to the highest level (69%) in the five years since the study began. Virtually all families exercised cost-savings measures, including living at home (51%), adding a roommate (55%), and reducing spending by parents (50%) and students (66%).
• In 2012, families continued the shift toward lower-cost community college, with 29 percent enrolled, compared to 23 percent two years ago. In fact, overall, families paid 5 percent less for college compared to one year ago.
• 35% percent of students borrowed education loans to pay for college: 25% borrowing federal loans only, 9% using a mix of federal and private loans, and 1% tapping private loans only.

Telephone interviews about how families paid for college in academic year 2011-12 were conducted with 801 undergraduate college students, ages 18 to 24, and 800 parents of undergraduates.

Kay Steiger also flags this chart, which I think illustrates the issue a little more clearly:

This chart shows the majority of students attending college do not borrow money to pay for their college, although I think if you were to dig a bit deeper you would see this is for two very different reasons. One - a lot of people who attend college right now are simply more wealthy and don't necessarily have to borrow to pay for their education (which then also means more and more people simply aren't attending college because they can't afford it).

But the second part is equally important - many students have most likely shifted their education away from public and private four year universities towards more more affordable community college options.

So the majority of students attending college this year might not be taking out loans, but for two different reasons, both of which point to college being expensive enough that it's forcing a significant number of students out of traditional four year universities.