Artist just can't stop loving the King of Pop: there have been not one but four different works featuring the mighty moonwalker on show at Frieze at some point this week. Homage, irony, bandwagon-jumping...or simply taking the Michael? Clockwise from top left: Jonathon Monk's Black Bubbles, 2009, ink-jet and acrylic on canvas, 35,000 euros, at Yvon Lambert (D3)...