Unable to create label format for membership card
I ended up creating an extension for a professional organization to handle this - ingredients:


function membershipcards_civicrm_tokenValues [you must create the tokens e.g.  $value['membership.type'] and $value['membership.status'] - I have 'see Example from Lobo' in my NOTES: https://civicrm.org/node/480
Then I have a Task: class CRM_membershipcards_Task_IssueMembershipCards extends CRM_Contact_Form_Task {
So that you can Find -> Advanced Search Contacts -> select them and then in the -actions- you can pick: Print Membership Cards
Then in the postProcess for that -action- I swap out the tokens and I re-use much of core mailing label bits - this is everything I want on the card:     



  $formatted = $row['addressee_display'] . "\n" .
  $row['contact.homestreetaddress'] . "\n"  . $row['contact.homecity'] .
  ' ' . $row['contact.homepostalcode'] . "\n" . "\n" . 'License #: ' .
  $row['external_identifier'] . "\n" . $row['membership.type'] . "\n" .
  $row['contact.activityskills'] . "\n" . 'Start Date: ' .
  $row['membership.startdate'];


Eventually that gets passed onto self::createLabel($rows, $fv['label_name']);

Then my own function createlabel has all my custom layout for this organization: 
XY positioning of the details, font, logo (watermark) placement, authorized signature. 

Hope this helps! You could just create the Tokens and then you might be able to get at them into a template - however if you really want control over layout/looks - you'll need your own createlabel.