This doesn't affect my own current small sites, but does affect these forums, and may affect my client sites. Seeing too many 'New' flags all over the pages can be irritating, so a 'Mark as Read' option would be very useful to kill the alerts for threads you just don't want to bother with any more.

Further, thread and/or author blocking would be good, so you can hide stuff you find boring or annoying, with perhaps a tab to see the hidden stuff a bit like 'My Drafts' does.