This week Synology released the public BETA of Disk Station Manager (DSM) 4.1. I'm not copying the release notes into this post as you can read them over at Synology: http://www.synology.com/support/beta_dsm4.1.php?lang=enu
So how do you install the BETA on your DS?
First you have to download the firmware for you DS (http://ukdl.synology.com/download/beta/DSM4.1_beta/). Now connect to your DS and open the 'Control Panel' and click on 'DSM Update'.
Hit the 'Manual DSM update' button and select the firmware you just downloaded and follow the instructions. Wait a little while and after the DS is rebooted it's running the DSM 4.1 BETA. After the upgrade you can upgrade you packages with the 'Package Center'.
Please read before upgrading!