There is no statistical significance to applying in R1 versus R2. Your odds are not necessarily different nor does the number of applicants admitted necessarily change. Each year is different, so it is not easy to make comparisons or have statistics for each round at a school hold true year in, year out. In each admissions cycle, the applicant pool will change as will what the school is looking for in terms of its class profile and background. This year is a highly competitive year due to an increase in applications at many schools. Next year, schools might approach how they evaluate applicants differently or alter their class sizes/demographics based on the previous year's class. I realize this is probably not much help, but it is not as simple as R1 with visits versus R2 without visits--there are so many other factors at play.
I think you need to focus on your interview at this point, see what happens. If you want to submit 1-2 applications in R3 to a couple of schools you feel you would be happy at, then do that. Otherwise, wait until next year and apply to a mix of schools in R1--top 15 and safety. That way, you know you will be in business school in fall 2011.
Good luck,
Lisa