We are definitely having some oddities with the New Post indicators. I've been noticing some issues as well, although different ones from what you're observing. I'm a Netscape user. Editor, who would be the one to ask about this issue, is taking a much deserved break from all but the most urgent emergency issues (like site outages) until the beginning of next month. If we're still having problems at that time, I'm sure he'll address them then.
I'd be interested to hear if Internet Explorer users are experiencing any similar difficulties.
Kiarnit, Volunteer Coordinator and Moderator for The-OP.com