Surprise was originally a pony from Generation 1 of My Little Pony--you know, that other good one. Back in that day, Lauren had the dream of getting hold of My Little Pony and writing for it. She drew the G1 ponies in her own style--which we've come to know as the style for the show today. They're hard to find now, but if you look hard enough, you might be able to find those old pictures. Anyway, fast-forward to 2010 or so. Lauren finally gets the chance to work on My Little Pony: Friendship is Magic, but Hasbro has lost all the copyrights on the old G1 ponies. Not letting this slow her down, however, she took Surprise's personality and fused it with her designs of both her old Surprise concept art and that of a Generation 3 pony, Pinkie Pie. And that's how we got the Pinkie Pie we know and love today. It is also worth noting that Surprise's wings went to Fluttershy, who was originally an earth pony named Posey.
But you know what really scares me? If Romney wins, he will likely campaign against us bronies. Ever since I became a brony, I've been truly happy. I don't want some fucking Republican dickbag taking my happiness away. If he does this, I might take the risk of insanity by learning dark magic and teleporting myself to Equestria.
Actually, Pinkie from "Seeing the Pattern" was based directly off of Surprise. The white pegasus you see above is actually the G1 pony that Pinkie Pie was based off of, which is why all G4 renditions of Surprise look so similar to Pinkie.