Thankfully, Lyst.com just rolled out Runway Tracking for the Spring 2012 collections. Within hours of the shows, images of each look were uploaded to Lyst.com and users could simply click to add individual items to their individual lists. When that item hits stores, users will get a notification and can click to buy—no handwritten calendar notes necessary.

Oddly enough, this digital platform mirrors the dynamic of the world's largest real-life dressing room: if enough people add the Alexander Wang skirt on one user's list to their own lists, it's the digital equivalent of a glowing compliment while they're trying it on. "It's reinforcement, social validation," says Morton. "A lot of times, that sort of validation leads to purchase. That's something we didn't expect, but have been seeing a lot of."

It's also an added bonus for retailers (Lyst.com works with hundreds, from The Row to Ralph Lauren), who can get a snapshot, months ahead, of how certain pieces might fare in the marketplace. And with users numbering in the hundreds of thousands, and doubling before fashion week, there's a strong pool from which to draw. Morton recalls a golden jacket from a few seasons back that caused a frenzy of excitement after its debut on the runway, but was never actually produced. Only after there was outcry over the item's absence did the designer go back and make it. "Hopefully, with Runway Tracking, that mistake wouldn't have been made," says Morton.