Setting Fields Using Rules I couldn't find the answer at How to change a field value with a Rules Action?, so instead of necroing that I figured it would be better to ask here.

I have a Rule that, when a Taxonomy Term of a certain type is created, it creates a node of a specific type. I need the Rule to also have actions that edit a few fields of the node - there's a term reference field I need set to the Taxonomy term that triggered the event, and I would also like to set the body to some generic text (either the term name or "Lorem ipsum...").

I see no "Populate a Field" in the Populating a node reference field using PHP in Rules. I don't need the PHP filter, thankfully. 

Is this possible?
The action you are looking for is "set a data value". You will find that some values are easy to set with this and some are not. Install devel (if you havent already) and use the page array functionality to get the exact details about fields you want to fill in. Also make sure to have tokens/entity tokens available as that will make your life a lot easier for setting values in rules. If the field is multi value then you will need to start using variables, lists and loops to fill the field with data.