This article from engadget says the SDA will be available 2/13/2006 for $299.99 and the MDA on 2/20/2006 for $399.99 (pictures of the two are available here). This review in CoolSmartPhone.com discusses the features, pros and cons of the MDA (which is a more traditional PDA-style phone as opposed to the SDA which is more of a phone-style phone). WiFi, Bluetooth, GPRS, GSM and EDGE-capable!