I've noticed in the last weeks that it is hard to differ between the icons for new posts and not new posts if it is a popular thread. Perhaps a little amount of colour could help. For example a little bit red or orange in the icon for new post would make it a lot easier! Just a suggestion...
Not a bad idea - I'll look into it.
I finally got around to editing those icons - nothing too obnoxious, but a slight blue tint to match the forum colour scheme. Quite subtle, but I hope it should be a little bit easier to distinguish now.