If you are referring to the postbit, then yes. All you have to do is go edit that in your Styles & Templates area / Style Manager / Style Choice / Edit Templates
In Postbit Templates:
I use postbit_legacy so I'll use that for example.
Find <!-- post $post[postid] popup menu -->
This is the area towards the end of the postbit where it controls what goes in the popup menu.
<tr><td class="vbmenu_option"><a href="http://yourlinklocation.com">Your link text</a></td></tr>
Looks good!
What I want to do is add a link to the user's gallery page (PhotoPost). This just needs the user number being included in the user gallery root url. I don't suppose anyone has already coded this little routine?