I got my first shiny in XY last night :D
Shiny Skorupi!
I was using pokeradar, but not seriously hunting anything, just messing around. I didn't even use repels X_X
But poke radar'd my first Skorupi, then the second which I didn't even see where the grass shook, I just walked to a random spot, and then the third one was sparkle grass!
This is after three days of trying to chain for several other things and nothing.
Not a huge fan of Skorupi, but her color is really cool, so I think she may be sticking around :)
she's my second wild shiny (my only other being a magnamite in soulsilver that I didn't even know what it was when I caught it)
I have a handful of others, but they've all been trades (umbreon, vaporeon, quagsire, and gligar) or in game (dragonaire)
My friend who sits next to me at work has obtained 3 shinies - all random encounters.
first was Smeargle, then Octillary and Vanillite (spelling on those?)
Someone's lucky :|