I can only see four: the grey patch below the islet, the oddly-repeating golden tree directly below that, a reappearance of the golden tree with its friend the smoke-monster from Lost in the very front at the middle, and the golden tree again, this time with a fetching black hat scribbled-on, on the right directly below the rightmost patch of lights on the far shore. I've listed those in increasing order of obviousness, the final one being I'm afraid really hopelessly obvious.

Peter