It appears that Cygnett has already put up some iPad Mini cases for sale in Australia. One Aussie managed to get his hands on it and made a very cool video reviewing them! Check it out!
This video reveals that Cygnett has already made 2 different iPad Mini cases that are roughly 20 cm long and 13 cm wide and 1 cm deep. He also uses his artistic talents to determine that the iPad Mini will likely have a 16×9 aspect ratio (just like the iPhone 5 and iPod touch), with a 2 cm border around the screen (in keeping with the same border size as the iPad itself). He is guessing that the new iPad mini will have a 7 inch screen rather than a 7.85 inch screen. But really that is anybodies guess.
So if you live in Australia, keep your peepers open for one of these Cygnet iPad Mini cases!