Carol Tenopir et al. have published "What Motivates Authors of Scholarly Articles? The Importance of Journal Attributes and Potential Audience on Publication Choice" in Publications.
Here's an excerpt:
In this article we examine what motivations influence academic authors in selecting a journal in which to publish. A survey was sent to approximately 15,000 faculty, graduate students, and postdoctoral researchers at four large North American research universities with a response rate of 14.4% (n = 2021). Respondents were asked to rate how eight different journal attributes and five different audiences influence their choice of publication output. Within the sample, the most highly rated attributes are quality and reputation of journal and fit with the scope of the journal; open access is the least important attribute. Researchers at other research-intensive institutions are considered the most important audience, while the general public is the least important. There are significant differences across subject disciplines and position types. Our findings have implications for understanding the adoption of open access publishing models.