Eucalyptus 3.2 introduces a new user console, better troubleshooting and logging, better reporting and support for EMC VNX SAN arrays.
A lesser known fact is that the EBS implementation in Eucalyptus 3.2 no longer requires loop devices. In 3.2, we open sourced a new driver called DASManager, which stands for Direct Attached Storage.
DASManager allows you to use raw block devices like JBOD arrays, as well as LVM volume groups with Eucalyptus. You are no longer limited to 256 volumes per storage controller host. The maximum capacity is limited by the number of LVM volumes that can be created and the size of your disk.
You do need a separate disk, partition, or a volume group though. Here is a link to the documentation that explains how to configure the Direct Attached Storage driver for EBS storage.
You can always access the latest Eucalyptus documentation here.