I saw MOO 'socials' referenced a bit earlier. The verbs used (like 'hug <name>' or similar). In my experience (my first few years in the hobby were primarily MOO), those were always used in an OOC context.
So if a good friend logged in, I might type 'hug <name>' rather than 'p <name> :hugs!'
I, personally, never saw a game that used them as IC things because only the two people involved saw them and they weren't isolated to being in the same room (like Arkandel's MUD example).
I do use metaposing to supplement body language. Something like 'her shoulders round and tighten, in an almost defensive gesture.' Because similar body language can have different meanings... but while you'd be able to tell the difference IRL, explaining it in text is harder. So it's easier to give the context that someone would read 'in person.' I do also crack jokes (often at my character's expense) in poses.
My scene sets can be long. I know there was a joke at one time, 'Page long set? Must be an Auspice set.' 90% of the time it'd be in situations where an RP Room was being used and thus there was no desc, or the room we were in represented a very large area (such as 'The Park' but the scene itself was being done around a specific fountain). And no, it's not one page sans line breaks. I use line breaks, don't worry.
After the set, though, most of my poses tend towards the 5-8 line sweet spot... But it does depend on others in the scene. Mind, that usually only angles me to shorter poses. I generally can't be arsed to keep up with massiveposes for long at all.
...unless it was a gdoc with @Ghost. I don't know what it is about our RP, but we would have some long, descriptive poses. It was fun, but no one draws it out of me like he does. That bastard.