I know Khan Academy is not actually a school and therefore they cannot issue official Diplomas, nonetheless the creation of Diplomas just for informative purposes would still be great, same way they do at Zend. 

Khan Academy is not just a place to reinforce knowledge, here we can build pretty advanced skills in several areas. For example mastering all math skills is considerably laborious and would be an unequivocal sign of expertise and dedication. Many of my colleagues would be proud to display in their CVs or Linkedin profiles a link to their achievements in Khan Academy, but the  "Profile/Show Case" section currently looks a bit lame and childish.  

I think creating permanent links to Khan Academy diplomas containing all  mastered skills by each user would  be an awesome improvement (only for users willing to share it). This will considerably increase the diffusion and prestige of the Academy. Many companies (mine among them) value and assessed mathematical background on candidates. 

If you also think that this could be a great feature, I guess the next logical step should be allowing to upload personal avatars, so they can be included in the Diploma. 

Thanks for your hard work.