Moose 1.16 (and Class::MOP 1.10) will be out shortly, and it's mostly bug fixes.
Among the bigger changes ...
- Native delegation methods which change the attribute value now have explicitly documented return values. Before 1.15, a lot of them had implicit return values, and some of those return values were kind of confusing. Now we make a point of returning whatever the equivalent Perl builtin operation would return, and we document that.
- Native delegations have better docs in general.
- Some native delegation methods which required a string argument didn't accept an empty string, like
Array->join. Oops, that was wrong.
- Deprecation warnings have been improved. They're now more likely to find the right caller of the deprecated feature, some of the warnings have been improved, and we've fixed some cases where you got a warning when you were doing something perfectly acceptable.
You can take a look at Changes in git while the release makes its way to CPAN.
If you're using 1.15, you should probably upgrade to 1.16. If you're on an earlier version, you should consider upgrading too. As always, please test your code with the new Moose.