So far, I've been attacking this problem by writing reviews that cover a range of modules (templating tools, data caching tools, object-relational mappers). I'd like there to be a way to find out what the most popular modules are (by preference, not by download stats), but there is some resistance to this idea. A partial solution may be Leon Brocard's Module::CPANTS, which generates some metrics about a module and may eventually be able to give you some generally useful stats about danger signs or quality signs in a module.