Okay, so Threadless by Jake Nickell can be about the t-shirts if you want it to be, or it can be a book about an innovative little company founded by Nickell that, by allowing anyone to submit a t-shirt design and have it voted on, became not just a business success story but also created a flourishing online community and a legion of t-shirt wearers who feel invested in what they're buying.
I have to admit, on my first pass-through, I just looked at the pretty (and awesome) images, because the author and Abrams have done a great job of mixing up static shots of various designs with people actually wearing the t-shirts, in addition to a few photographs of Nickell and staff hard at work at Threadless Central. The title page shots that divide the book up by year are often hilarious. The t-shirts themselves make clear why Threadless is such a good idea: where else would you find so such a variety styles and approaches to art in a single book and think "wow" rather than "what an unholy mess?"
However, after you get over the fascinating eye candy, Threadless still fascinates because Nickell does a nice job of charting the company's origins and progress across a decade of change and development. Not only do you get a good sense of the challenges facing the company but also of the shifting nature of the online landscape in the 2000s, along with some wonderful insight into creative process. There are several pages that include a design and then the creator's explanation of their inspiration. The section on "crowdsourcing" and why Nickell doesn't like the term is interesting as well.
In short, there's enough meaty text here to satisfy you once you've browsed through the art. But I think that I've given you more than enough words about Threadless. Check out these images, with more to look at here.