New EBS (AWS) volume type: General Purpose (SSD)
"General Purpose (SSD) volumes provide the ability to burst to 3,000 IOPS per volume, independent of volume size, to meet the performance needs of most applications and also deliver a consistent baseline of 3 IOPS/GiB. Provisioned IOPS (SSD) volumes can deliver up to 4000 IOPS and are best for EBS-optimized instances. Magnetic volumes, previously called 'standard volumes', deliver approximately 100 IOPS on average, with a best effort ability to burst to hundreds of IOPS."
The EBS Pricing page (http://aws.amazon.com/ebs/pricing/) currently makes no mention of General Purpose (SSD) volumes.