Google’s Music service is only available in the US right now, and its Books store service only serves up free, public domain titles elsewhere in the world. Needless to say, their associated Android apps are US-only for the time being. So, why did my Android handset decide to offer me downloads of both this morning?

Yes, when I checked my Nexus One this morning there were two new downloads available: Books and Music, despite the fact I had neither on my phone already. Of course, I downloaded them right away – and they both work fine. I can’t actually use Google Music, but Google Books synchronises the public domain titles I have in my library and lets me read them.

I’m not alone, either. A search of Twitter reveals a number of other users who experienced the same thing today, although unlike me they seem to have been unable to actually download the apps.

So, what’s happening here? Well, it could point to an imminent launch of these services, but I wouldn’t hold your breath. All the users we’ve found so far say that they have a Nexus One or Nexus S handset – official Google phones. As we reported when it was released, the Nexus One had Google Voice (another US-only service) installed but ‘hidden’ on handsets outside the US. It appears that Nexus phones get all these apps whether you can use them or not – only revealing themselves when an update is available on the Market.

Has Google Music or Books appeared as an update for you on your Android handset? Let us know by leaving a comment – we’d love to know if this is more widespread than just Nexus devices in the UK.