Uggs have finally started fading, replaced by motorcycle stompers, horse riding boots, and Wellies lined with extra socks. But in their place comes another vision of slouch: flannel pajama pants in plaids and prints, flapping in the streets. We've seen the pants in Starbucks, at the Angelika Cinema, outside Chanel in Soho, uptown by the Met, and yesterday, at the Brooklyn Academy of Music. The fashion transgressors wearing them are young (15 - 30), accessorized (a faux Louis, a real Stam, a boy with a Prada duffel), and usually paired with a cropped jacket and huge sunglasses. One blown-out blonde wore hers in Dean & Deluca with a Michael Kors cable knit tunic and - despite the weather - London Sole ballet flats. The upside: the pants do compliment the Alaskan hunting vibe everyone's got with their trapper hats.