blueSLR is a new company that are introducing a new way of controlling your DSLR using your iOS device wirelessly over Bluetooth using their dongle that attaches to the side of your DSRL. All you need is a Nikon DSLR, blueSLR's free iOS app and of course a compatible iOS device like the iPhone 4, iPad, iPhone 3G/S and iPod Touch. As of now blueSLR do not support other DSLR brands except for Nikon but will soon support the Canon brand. You can see if your Nikon DSLR is supported here. Your photos will be tagged by the built-in GPS module so you will know exactly where you've taken your pictures.
You can control the shutter release and auto-focus timing using the blueSLR app. You can now pre-order yours for $149 and expect shipping on December 20th.