Apple made the unusual move of pre-announcing HomePod back in June 2017, promising that the speaker would be available by Christmas 2017 (and failing to deliver on it). But the HomePod is out now, having launched in the UK, US and Australia on 9 February 2018. It will come to France and Germany in spring 2018.
The HomePod meant that there was a lot of talk about Apple's smart speaker in the run up to the launch, but rather than building anticipation as to which smart features the HomePod would offer, it became obvious early on that Apple's focus with the HomePod was primarily audio quality. The HomePod is a speaker with the benefit of some Siri features built in, rather than a voice activated assistant that just happens to play music.
The main issue facing HomePod is people's expectations of what a smart speaker should do and the fact that many already own a smart speaker. Apple is banking on the fact that what people really want is a good sounding speaker, and that they are happy to spend money to get one.
The HomePod costs £319 in the UK. That's a lot more expensive than the nearest rivals, in part to reflect the superior speaker quality.