Long awaited firmware update just announced:
http://gizmodose.com/d-link-sharecenter-pulse-dns-320-2-bay-network-storage-enclosure.html
Unfortunately we'll need to buy a DNS-320 to get it.  
Different hardware (faster CPU), similar pricepoint to the DNS-321.  Reports are folks are getting transfers in the 400Mbps range (40MB/s?) with it on a GBE network.  Same price.  4x performance gain.  Something tells me we're never going to see any DNS-321 firmware updates.
Damn straight you're not. The product was already EOL'd in Canada earlier this year. It's an orphan.