Over at Dirk Witte in the Netherlands there are currently 3 different types of Tyros 3 available for pre-order..
Tyros 3
Tyros 3XL
Tyros 3XXL
List This could indicate that there might actually be a 76 key version... just add your own specualtions to this thread... Dirk Witte is one of the most renown Synth sellers in the Netherlands.