I think the 'popcorn' word sometimes refers to the really heavy texture used for ceiling work where there are actually specs of styrofoam or something in the paint. Major craggy stuff. I'm just talking about normal light speckled wall texture, mostly used to help hide imperfections in the taping/mudding job.
Since I'll be doing my own tape/mud and this is my first time, I'll probably need all the hiding I can get.
Poking around on the web some more, it sounds like I need to experiment with different techniques and see what I like. If I can avoid spraying, I will. Since I'm going to be doing double drywall with green glue on most of my side walls, I'll have a lot of space to experiment with. Once I have the first layer up, I'll try some different roller approaches on the first layer of drywall, then wipe it off (or at least smooth it down).
We'll see what happens. Thanks for the help.