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I just downloaded the smooth sounds of Al B. Sure!, the In Effect Mode album, on iTunes.

And as I'm sitting here grooving, scrolling through the stuff in my playlist, it occurs to me that iTunes apparently has at various times gone all TiVo on me and stuck crap in my playlist that I never downloaded and don't particularly want.

Does iTunes always do this?  Does it do this to everyone?  Did I inadvertantly click on the "please stick crap I don't want onto my playlist at random" button? 

Can someone explain this?