Some of the difference could be due to your browser, and cookies/cache settings.
Do you check the little "remember me" box when you log in?

That might make a difference too.
I'm always logged in when I am here, so I never really see the Today's posts the way you mention....


If there are specific threads you want to follow , you can click the Thread Tools drop down - and subscribe to that one.
then you will get a screen asking what kind of notice you prefer.

* this might be the easiest way -
You can bookmark/favorite a forum, thread or page- then it is easy to find always.