Ok, I could not get it to work in the postbit or postbit_legacy template, but here is what I did do to get it to work:
Edit your postbit_onlinestatus template
add this at the end:
Code:
<!-- Start Show Text In Postbit if User is Online -->
<br />
<div class="smallfont">
<if condition="$onlinestatus==1"><b><font style="color: #486FA2;">See This text</font></b></if>
<!-- /End Show Text In Postbit if User is Online -->
That will put the text at the bottom of your postbit, but none the less, it works. You can of course edit the font to match your needs.
Mark