I'm not getting the e-mail notification of new posts to threads in which I have posted. Does that feature still exist? Is there something else I must do now to get those notifictaions?

Go to your control panel
Along the left hand side towards the bottom there should be a "Email Settings" link.

Then again towards the bottom should be this question:
Enable 'Email Notification' by default?
Enabling this option will automatically subscribe you to receive email notifications about (1) new messages under any topic you started, or (2) new messages under any topic under which you've posted a message.

Double check that setting as it seems to be working for me.

Thanks. The e-mail options were all deselected in the Control Panel. I went ahead and checked the appropriate. I'm sure that will fix the problem.