A while back I wondered what the heck a Trixie was. A kindly anonymous coward posted a link in my comments that's worth repeating here: http://www.lptrixie.com/. As far as I can gather, they're a particular yuppie subset, with an affection for Jettas, labrador retrievers and looking like their friends. From the informative FAQ:
As chain coffee stores like Starbucks have begun to truly define neighborhoods, Trixies have come to embrace this trend for several reasons: First, Starbucks is an impressive place to buy your coffee, plain and simple. With the myriad of different adjectives you can use to define your latte, you're bound to stand out and make a statement about how smart you are. Secondly, Starbucks is not cheap. While many Trixies exist on a shoestring budget (due to the need to buy the most impressive clothes and showbox apartments), holding a Starbucks cup silently tells your coworkers and best friends that you've made it.
Here, also, is a handy day in the life of a Trixie. These people have gone to a tremendous amount of work on this site--there's an impressive amount of content.