Add the ability to ignore users
I'd really like the ability to ignore comments by particular users on a per-user basis or simply choose not to see comments at all as a preference or interface mechanism (see related). Particularly on meta, some comment threads are distracting to the actual question/answer dialog. It would be nice to filter out some of the more distracting commenters and/or hide the comment display entirely to make it easier to read the questions/answers.
Waits for inevitable annoying comment threads to start...
Alternative: what if, instead of simply removing the comments, it worked more like SO where I only see a certain number of comments unless I expand them all. In this case it would hide the comments from people I'm not interested in or beyond a certain number that I've chosen but give me the ability to expand the comments as desired. This would keep the context available if I'm interested in following a discussion but keeps the comments to a manageable level. This behavior could be specified by user preference but would default to showing all comments.