No one knows exactly what Taylor Swift will wear down the aisle or when she'll host her bachelorette party . If the singer's little white dress for her second New York City night out this week is a hint, her pre-wedding outfits are as likely to start spring bridal trends as her look for the official event.

For a May 12 dinner at Via Carota, Taylor Swift followed the previous evening's bejeweled Valentino dress with a stark white mini from Retrofête. It had all the makings of a late-spring bachelorette party dress: long-sleeves and a mock-neck for the transitional weather, plus a flirty pleated skirt for dancing at a dive bar on the east side. Brides-to-be only needed minutes after Swift's dress appeared online to update their own bachelorette packing lists in response.…