Hi
It's already available for long time:
1) When only reading the topic (thread) you can see such list of buttons at the top and at the bottom also:
REPLY NOTIFY MARK UNREAD SEND THIS TOPIC PRINT
then just press NOTIFY and confirm it.
2) For the topics you replied (or started) you can also manage the announcements following this path in the menu:
PROFILE --> Modify Profile --> Notifications and Email --> Turn notification on when you post or reply to a topic (and also other options which are located there)
