The ARL Annual Salary Survey 2006–07 has been published, and it can be purchased from ARL.
Here's an excerpt from the press release:
The 2006–07 data show that ARL librarians’ salaries outperformed inflation. The combined median professional salary in US and Canadian ARL university libraries was $59,648—a 4.5% increase from the previous year. Over the same period, the Consumer Price Index rose 4.1% in the US and 2.4% in Canada. . . .
Gender-based salary differentials persist in ARL libraries in 2006–07. The overall salary for women in the 113 ARL university libraries is 95.7% of that paid to men; this figure compares to 95.5% in 2005–06. While the data show a marked closure of the gender gap in ARL libraries over the long term—in 1980–81, women in ARL libraries were paid roughly 87% of what men were paid—the data also raise the possibility that the closure has peaked, and that a 5% gap between men’s and women’s salaries may persist.