Here is a quick update on the WiiKey specifications and release date from the new official site

Direct boot of Wii backups (like originals)
Direct boot of GC backups (like originals)
Direct boot of homebrew in GC mode
Supports all currently available console and drive versions (including the D2B chipset)
True sophisticated upgradability via DVD/disc (future proof, expect cool features to come)
Direct boot of different NTSC region Wii games on USA and JAP consoles
Partial support for different region NTSC games on PAL consoles
Supports different region GC games (partially without swapping)
Supports multi-disc games for BOTH Wii and Gamecube
Supports DVD-R / TRUE DVD+R and +RW support (no bitsettng required)
Improved read settings for recordable media
Built-in audio fix (for games using streaming, no patch required)
Supports full-size 4GB DVD for Gamecube homebrew
Stealth mode
512 byte EEPROM to store configuration
4 wires & quick solder interface
Unique disc backup application via SD-card
Compact design, best quality components, rock solid high speed controller
Professional ESD packing