For many years now Revit families have been called Components. The 2010 and 2011 release help documentation calls them Loadable families. I don't remember if 2009 started calling them this or not.
The ribbon offers us the Component tool however.
I see how loadable is more descriptive of how we get them into a project. I find it interesting that we have to think of them as components when we want to place them but as loadable when we need to design them and add them to a project. I suppose it isn't that hard to blur the distinction.
Language is fun!