Accessing POM List-style Elements from Interpolation Process / Parameter Expressions
The main use case for this currently is this best practice discussion. The syntax discussed in that document for referencing dependency versions should be generalized to allow references to any list-style POM element, including plugins, repositories, developers, contributors, etc.
In general, I think the most expression language-neutral syntax would be something like:
${project.dependencies["org.apache.maven:maven-artifact"].version}
This syntax is similar to OGNL, XPath, and (I think) the JSP expression language.