Mass Storage Devices are quickly merging into one, take the PQI Intelligent Stick, which is USB and SD card compliant for example. Power Quotient International claims the converge of technology actually enhances performance. The size of the SD/USB combo is the same as non USB compliant Intelligent Stick. A 512MB version will be available by end of April (about $35)with a 1GB version in May. Source: Digit-Life.com
