I want to add my 2 cents on this. Can we get the default comments to mimic the activity stream?
I’ll have a try and see what it looks like. I think it’d work but we’d have to keep the “posted at” timestamp more visible like it is on blog comments at the moment.
@djpaul – a more informative title on your post might help, rather than the general “theme designers: contribute to core”
How about we start a group for designer contributions and duscusions of UI and UX 
Did raise that a while? back, not sure it inspired much interest, but you would need to define whether one was dealing with general UX /UI or the default theme, from a theming point of view not child theme necessarily , but full on theming some UI / UX is merited along with other issues such as identifying markup that needs removing from core if applicable and aspects such as better handling of activity_action which isn’t fun to deal with from a frontend perspective.
@hnla there was something about BP.org UX/UI in Ninjas forum topic and writeboard, but haven’t read one specific re bp-default. Is that in trac and/or discussed in BP IRC? In any case, count me in
If people want to play a role in the development of BuddyPress, the best way is to either put a patch up on trac, or attend a dev meeting and let us know you are interested. We can find you a task for your skills.
If someone wants to make a discussion group on this site, that’s cool too. But any enhancements or ideas need to be fed back into the trac, so we can keep track of them 
Here is some real basic styling no colouring just indenting in the traditional style of comments not the activity stream version for now figure we may as well get traditional down first?
`ol.commentlist, ol.commentlist li {
list-style: none;
margin: 10px 0px;
}
ol.commentlist .children {
margin-left: 20px;
}
`
We could of course do borders around those but that will start with some simple indenting.
