Jeri, I thought I was the one who had the unintended skill of killing threads! *G*

Rick, you're right that newcomers' posts aren't routinely ignored by virtue of that status. But we relative newcomers sometimes do have the experience of posting some silly little comment to a BS thread full of other silly little comments and being ignored --- kinda like joining a small group chatting at a cocktail party and having them talk among themselves and not acknowledge anything you say.
This is not really rudeness, though, I think. In a non-informational thread, posters often do address their remarks to specific other posters, and it's no surprise that there often arise sub-conversations among "Mudcat pals" within the general thread. This is when the thread is more like a chat room than an information sharing session.

Not getting a reply to your post may mean folks didn't find it interesting (or found it offensive), but it also may just mean they didn't feel they had anything important to say in reply--and that you haven't established a personal connection with them such that they feel like bantering with you--yet.