vBulletin 4 Request - Cookie based post marking....

[Mark.B]

The whole idea of 'New Posts' is to show posts you haven't read.
If it shows you posts you've already read, it's completely pointless.

If you have members who want that functionality, change the usergroup permissions on Today's Posts instead, so it shows to members. Then they get a list of all posts in the past day (or whatever time period you want basically), unread ones are bold, read ones are non-bold.