I see five top-level comments by you in the current version. Could they be hidden under the "load more comments" button? (They aren't for me, but it could depend on the sort order.)
The comments are visible to me.
FWIW, what I would do in such a situation is click on the permalinks from the cache. Regardless of the situation, that would be a useful additional piece of information to show us. If the comments have been deleted, that would yield a confirmation. An intermediate possibility is the comment would still exist at their permalinks while not appearing on the post. But then the permalink would be more useful to us than the cache.
click on the permalinks from the cache
What's a permalink from the cache, and where would I find it?
When I look at LW, each comment has a line of links at the bottom: Vote up | Vote down | Permalink | Parent | Report | Reply (illustration by cata). When I look at your google cache link, it has all of those links, except Report, probably because google is not logged in. (And links from the cache go to the real pages, not to more cache.)
I was googling to see if I'd already posted some stuff on LessWrong, and I found it in a web cache, but not on the site. Compare Google's Sept. 8 2010 cache of a LessWrong post to the version now on LessWrong. Everything between the comment made by MBlume on 20 April 2009 02:58:50AM, and the comment made by Alicorn on 19 April 2009 10:11:55PM, is now missing, including all 5 of my top-level comments, and some top-level comments by JulianMorrison.
I didn't delete them. Does anyone know what happened to them? Is this happening to other comments?