It means that which is:
• totally ecstatically wondrous, across every universe in existence
• endlessly joyfully amazing, throughout the world, and beyond imagination
• full-on orgasmically blissful, forever and ever, to infinity, and beyond
The TV shows Castle and Firefly are so intense, they are Triple Rainbow, All The Way Across The Sky."
The movie Serenity is so vivid, it's Triple Rainbow!
Nathan Fillion is so awesomely spectacular, sexyhotmessgorgeous, and brilliantly talented, his fame is sweeping across the nation, and over all the world! Nathan Fillion is Full On Double Rainbow, even Triple Rainbow, All The Way Across The Sky!