The Google wireless headphones appear to be for employees as it's now been pointed out that they are likely a replacement headset for internal use, as Google hands out headsets for employees to use at work. A current model that is said to be in use by employees carries a black color and is a wired headset instead of wireless, complete with an external microphone for talking during voice calls or voice chat scenarios. You can see this pair of headphones below which looks somewhat similar albeit a little more outdated in the design department.
While it might have been exciting to entertain the thought that Google would be releasing a pair of wireless Bluetooth headphones for consumers, it makes a whole lot more sense that they would simply be providing headphones for employees to use internally so they don't have to purchase them for employees or force employees to purchase their own and bring them to work. That being said, since these are just for internal use there won't be any way to obtain them. That is of course, unless you go work for Google and are issued a pair to use while you work there, in which case you'll have your very own pair that shows you were a Google employee.
Now that this mystery seems to be solved, it might beg the question for some as to why Google doesn't release a consumer-facing headset? Google products are usually loved by quite a few consumers especially now that they have been putting out more hardware and advertising its existence. Quite simply, Google probably has no desire to produce a pair of headphones that consumers can actually buy. Not because they're not in the business of making hardware, as they have plenty of it to show that they have interest in hardware products, but because a pair of Google headphones for consumers might come across as a product that isn't really needed. Whatever the case, those that have shown up at the FCC recently seem to be an employee-only deal, but consumers who liked the idea of having a Google headset can always take to a DIY project to turn an existing pair into whatever they like.