I haven't figured that out, i think you just have to look at the "new comments"and she

See if it's a reply to your comment... it's not like Facebook where you get notifications 

Bookmark your posts.  That little green flag at the bottom of the post is the bookmark.  Then you can look at your list of bookmarks and keep up with active threads. 

I just keep a tab open with a thread for a couple days and look for updates. I wish there was a better way though.

For replies to your own blog it will tell you that there are new comments if you look at your blog list.

Each forum will update with the number of comments since you last entered that forum.   There is not an easy way to identifiy if a comment by  you has been replied to in forums. every time you enter StepTalk.   As far as I know anyway.

If you go to the main forum screen you can see which forums have new comments since you last entered.  Inside each forum each discussion topick will also show which ones have new comments since you last viewed the content of that forum.

I know, a master of the obvious comment but... that is how I identifiy what may have been updated since I last looked.

Search for your user name. It will show all comments you have made by date, then you can check if anyone replied.