I created a user taxonomy called “Company Types” which shows nicely on user profiles as a checkbox list.

/* Register Taxonomy */

function piklist_custom_taxonomies($taxonomies)
  {
    $taxonomies[] = array(
      'object_type' => 'user'
      ,'name' => 'company_type'
      ,'configuration' => array(
        'hierarchical' => true
        ,'labels' => piklist('taxonomy_labels', 'Company Type')
        ,'show_ui' => true
        ,'query_var' => true
        ,'rewrite' => array(
          'slug' => 'business-directory'
        )
        ,'show_admin_column' => true
      )
    );

    return $taxonomies;
  }

/* User Fields */
piklist('field', array(
	'type' => 'checkbox'
	,'scope' => 'taxonomy'
	,'field' => 'company_type'
	,'label' => 'Company Types'
	,'description' => 'Choose only two categories.'
	,'choices' => piklist(
		get_terms('company_type', array(
			'hide_empty' => false
		))
		,array(
			'term_id'
			,'name'
		)
	)
));

I’d like to know if there is a way to group the terms as follows and not just a flat list of parents and child all with checkboxes:

ParentTerm#1 (no checkbox)
[]Child#1-1
[]Child#1-2
[]Child#1-3

ParentTerm#2 (no checkbox)
[]Child#1-1
[]Child#1-2
[]Child#1-3

Any lead is greatly appreciated.