I was doing some playing around with defining components in seam, using the components.xml to provide overrides, when I came across behavior I did not expect. What I am trying to do is use the components.xml file to effectively "uninstall" a component, or to put it in other terms, prevent the component from being installed.
Consider the case where you have a component (defined with the @Name annotation) that you want to prevent from loading, perhaps in a unit test or another conditional runtime scenario. You may think that you can do:
<component name="componentA" class="ComponentA" installed="false" precedence="50" />
Currently there is no way, but we've been arguing about this :-)