Apple has released further information about its HomePod speaker with Siri integration. It can be concluded from this that bluetooth is not mentioned as an audio source and that an Apple device is required to use the speaker.
The HomePod spec page states that the audio sources only include Apple Music, music purchased in iTunes, iCloud Music Library, Beats 1 Live radio, podcasts, and audio via AirPlay. As a result, it seems that, for example, it will be possible to play music via a service other than Apple Music, as long as it supports AirPlay. Making a direct connection via a bluetooth connection on, for example, an Android phone does not seem to be possible.
Support for Bluetooth 5.0 is mentioned in the specifications, but Apple does not use that technology for audio playback. The speaker also supports WiFi-ac. The system requirements also state that an iPhone, iPad or iPod running version 11.2.5 or later of iOS is required. According to The Verge, this is necessary to go through the setup process. The speaker will be released in the US, UK and Australia in a week. In the US, the price is $349.
Apple announced the smarthome speaker at its developer conference in June last year. The HomePod was actually supposed to be released in the same year, but the release was delayed.