Another non semantic markup used in Talk pages is the use of list bullets to visually separate comments. This does not happen in all discussions/sections as seen in live (not testing) talk pages. But it also not uncommon for some comments to actually use list markup for real lists.
I see that the Reply tool is smart enough to use either the colons or bullets to indent replies, based on the last reply (and not the comment that one replies to).
But there is a problem where one user marks his comment with a list bullet and the reply contains a real list. https://en.wikipedia.beta.wmflabs.org/w/index.php?title=Talk:Dogs&diff=426772&oldid=426771#Bullets_and_lists
https://en.wikipedia.beta.wmflabs.org/w/index.php?title=Talk:Dogs&diff=426776&oldid=426775
IRL a user who puts a reply in a section where the ettiquete is "bulleting" and his own comment contains a real list, would not use bullets for indentation.