Let's say I have an animation with several text layers, all of which have the same font, color, etc., and I want to be able to change all of them at once. In After Effects I would just link all of their properties to one of the text layers using expressions, and then change the font, etc. in that one layer. Motion doesn't have expressions, so how could I do that here? (For other parameters, like scale, opacity, etc., I can just put all the texts in one group and affect things at the group level).
You can drag and drop the "Paramaters" from the Text>Format/Style/Layout tabs onto the Preview well (the little image icon) in the Layers tab... basically, copying/pasting attributes of 1 text layer onto another text layer.
You can select more than 1 at a time to drag and drop - just hold down the Apple key (this should work even if you toggle between the 3 subtabs).
"The deepest blues are black" - Foo Fighters
(this doesn't help me when I'm chroma keying!)