You have to add animators to the text properties before you can reference the attributes. IOW, spin down the text layer, select Animate>Tracking and then you'll have a property that you can point to with a pickwhip. Not all properties are available. You cannot, for example, animate the font size. You can, however choose text scale.
You can't animate font, either with keyframes or with expressions.
> Better still, is there someplace beyond the AE manual that has a reference for these type critters?
If you find such a place, tell us.
In a more general sense, there are a few really good places for getting more information about expressions, and they're all listed in After Effects Help, in context. For example, this page points to a few good places for the basics. This page links to several good places for examples.
Thanks, Rick. That opens a lot of doors.
How odd that they didn't provide the ability to reference fonts. Well, if I do find such a place, your first question should probably be, "What were you smoking?"
Thanks for the links. I can see there's a large community of people who share AE tips and techniques. I suspect it'll be a long time before I run out of resources.
> How odd that they didn't provide the ability to reference fonts.
In general, things that are exposed to expressions are things that can be animated. We don't provide the ability to animate (change over time) the font for a text layer.
I'm not saying that it's not a valid feature request, but that's why things are as they are now.
BTW, you can access fonts with scripting. We added that in After Effects CS4.
How odd that they didn't provide the ability to reference fonts.
It's not really odd... It pretty much boils down to what Todd said. Aside from that, with all such things, it needs to be "safe" in a technical sense. Font handling is quite tricky and only gets more complicated with more custom formatting and animation. I'm sure everybody at the AE team is aware of this long-standing request for rigging fontface selection and specific formatting parameters, but it no doubt is more complex than it may look at first sight...
Yeah, I've never coded for Macs but the font API in Windows is a fiddly pain in the posterior. My comment about it being odd wasn't intended as disrespect, rather quite the opposite. After Effects does everything but cook breakfast for you (it may even do that, there's parts of the manual I haven't read yet), so it was just surprising as I figured there was nothing this beast couldn't do. Even so, the tip about animating text properties and scaling the font is a nice trick.
Thanks for the scripting link. Been looking at the expression stuff the past few days, which is pretty cool, so I'm looking forward to exploring the possibilities with scripts as well.