WebGUI is in the process of moving to Moose, and I've spent the last few weeks just learning Moose and writing perl.  It has been a very good time. You can see the work that I've done in the git repo in the WebGUI 8 branch:

http://github.com/plainblack/webgui/tree/WebGUI8

WebGUI::Definition provides two sugar methods, property and define, that replace the old definition subroutine/data structure, and it sets up the meta class for properties.  WebGUI::Definition::Asset builds on WebGUI::Definition with just another meta class and property class.

Here's where the hang up comes.  What used to be AssetAspect is now a Moose Role.  Each Role should have all the same sugar and meta class as a regular Asset, but doing this:

    use Moose::Role;
    use WebGUI::Definition::Asset;

makes for Moose puke:

    WebGUI::Role::Asset::RssFeed already has a metaclass, but it does not inherit WebGUI::Definition::Meta::Asset (Moose::Meta::Role=HASH(0x9781a78)) at /usr/local/share/perl/5.10.0/Moose.pm line 160