Today the leaks have been on a roll, the latest OS is for the Curve line 8520 & 8900 version 18.104.22.1681 via BBLEAKS.
You can Pick up the OS at the Following Links”
Curve 8900: http://www.multiupload.com/LUK7C60SZY
Curve 8520: http://www.multiupload.com/J8ON56OZ4I
Warning: Remember this is a BETA OS not official, If you do not know how to upgrade your BlackBerry OS please start by reading this step by step guide. Don’t forget to delete the vendor.xml file located in c:program files>common files>research in motion>apploader to install it on a different carriers device. Do not download and install these updates if you don’t know what you’re doing. Incorrect procedure or just bad luck could render your BlackBerry inoperative