Not a studio to fan the flames of gossip or anything, the guys at Rare have taken it upon themselves to create a selection of "Viva Piñata vs. Killer Instinct" Vision Cards for use with Viva Piñata: Trouble in Paradise.
Found on Rare's official site, this is sure to keep the rumors of a new Killer Instinct alive and well. According to Rare, if you use these cards by showing them to your Xbox Live Vision Camera, a KI Piñata will appear in your garden. The selected cards portray Fulgore, B. Orchid and Tusk.
More unique cards to be printed out and shown to your camera have been promised in the future. Whether you choose to take this as more evidence in the ongoing KI rumors or not, it's still a really cool idea.