This is the code shows how to hide the remove button and add the new icon instead.
<style type="text/css">
.tagbox-remove{
display: none;
}
.tagbox-icon {
position: absolute;
display: block;
width: 16px;
height: 16px;
right: 2px;
top: 50%;
margin-top: -8px;
opacity: 0.6;
filter: alpha(opacity=60);
}
.tagbox-icon:hove{
opacity: 1.0;
filter: alpha(opacity=100);
}
</style>
<script type="text/javascript">
$(function(){
$('#tb').tagbox({
tagFormatter: function(value, row){
var icon = '<a href="javascript:;" class="tagbox-icon icon-add"></a>';
return value+icon;
}
})
})
</script>