Have you subscribed to the thread and selected the frequency of email notifications you'd like to receive when new posts are made?
For those not familiar, you can "subscribe" to any thread, under the "thread tools" drop-down menu when you have the thread open, which will help you keep track of threads you're interested in following.
After you select "subscribe to this thread" you'll be prompted to pick whether or not you'd like to receive email notification when new posts are made to the thread. If you do want to receive those email notifications, you can also decide on how frequently you'd like to receive them (daily, every time a new post is made, etc.). Accept the choices you've made and then you should be all set.
You can also modify your thread subscriptions at anytime under your User Control Panel.
Kooki, does this help you at all or are you having a different problem?