Hmm, I had my Blockchain wallet open and I heard 3 tx beeps in a row.... I got 3 payments from those lucky blocks, yet I unplugged my miner a few days ago... mind you I only had about 45 GH/s on the pool, but still... Is my unplugged miner ghost mining?

Its how the payouts work, it takes 500% of average expected block time to reach full mining and about the same for all your shares to expire. Right now that's about 11 days or something via napkin math.