With the One lineup (particuarly the One X and One S), HTC really ratched up its focus on design. The One X is easily one of the best looking Android smartphones on the market today. The problem is that the majority of consumers prefer to use cases on their phones, which ultimately hides a lot of the design work that HTC and other companies put into their devices. There's also the problem of determining what color to launch with a device. You can't have an infinite number of colors and the trend lately has been towards putting out fairly conservative colors. This further amplifies the customer use of cases, which once again hides a lot of the design work that HTC and others put into their devices.
Apple took matters into its own hands with the bumpers for the iPhone 4 - providing some protection while not obscuring too much of the design. Nokia is similarly well known for doing this with its phones for a while now. HTC is following suit and will be shipping its own minimalist cases for the One X.
These things don't offer any protection for the screen, but they snap on the back of the One X while still allowing some of the design to shine through. The cases will be available a variety of colors and designs, but we got some hands on time with an orange and blue case. No word on pricing or availability.