Many forums have the function to look at the posts that were written from the last time they visited the site. So you would just click on the link and it would show you what has been posted in every forum since the last time you came to the site. This would be really handy. 

I second this one.  Some show the new posts from within threads, others show new posts for the entire board grouped by threads.  I prefer the latter for this board.

 I've heard a few people ask for something like this. It's on our list to check out. Thanks!

It's not _exactally_ the same, but there is a link in the upper right of the page (not the banner) that has "posts I have not read". It won't show you posts since you logged in last, but it is a quick and easy way to see what you haven't read yet.

 -A

Another way to do this, and keep new items grouped by thread, is to just click the"Active" link on the homepage. You'll get a list of all threads with recent activity. If a thread has something in it that you haven't read, the icon for the thread is bright and colorful; if you've read everything in the thread, it's grayed out.