Hey @xirclebox, thank you for your answer and references.
I have examined 3 main options for animations and came to the following conclusion.
SVG animations are a good fit for character animations.
CSS is an option for simple animations to a certain level of complexity.
GSAP is the bomb in terms of a full fledged easy-to-use api, performance and maintainability.
Have a look at one of the examples you referenced - antoniodinardo.com/TEST/confirmationpopup
A pretty straightforward button transition and the simplest isolated example I could find.
Now let's take a look at its actual CSS animation - antoniodinardo.com/TEST/confirmationpopup/css/sty…
Does it look anywhere reasonable to anyone to write this amount of code to get this simple button animation effect?
I don't want to even begin on what would it take to code CSS animations for this site for example - chekhov.withgoogle.com/alive
This level of complexity is what I'm aiming for. The character animations of this example were coded with morphSVG and the overall transitions were coded using GSAP. like others here - materialup.com/posts/tool/development/tween_max
Still, as a foot note I would say that we're lacking tools to provide us an easy workflow for designers to express their ideas and generate animation code using a simple GUI. We could do a lot better in 2016.