CPAN version numbers less that 0 don't always necessarily mean "alpha". For instance POE is still at 0.31 but many people have been using it in production code for years. If you look at the CPAN Testers report for the module in question you'll see it's been checked out on a large number of platforms with only a few hiccups.

Update: As adrianh mentions the docs are a good place to look for alpha-ness, and also check the "DSLIP" notation from the module list (which coincidentally does say that Devel::Coverage is considered alpha by the author :).