huh? We didn't have icons for the subject line on the old board.
...do you mean the smilies? They're still there. You have to make sure you have your 'message editor interface' setting in the control panel set to either 'standard editor' or 'advanced interface' to see them when replying, though.
In the User CP, go to the
Edit Options screen and scroll all the way down to find the editor setting.