There's been no official announcement, and it's not flagged up on the Amazon UK homepage -- you'll have to ferret through the site to find the UK Cloud Drive page. So I think we can expect to hear more come Amazon's press event on 6 September.
Pricing is pretty similar to Cloud Drive in the US. You'll get 5GB of free storage, then you can choose to pay to upgrade. For 20GB, you'll have to pay £6 every 12 months, then you can add between 50GB (£16 per year) and 1,000GB for a whopping £320 per year.
The Cloud Drive app for Mac and Windows is also available today. This lets you manage your files straight from your desktop. Once you've uploaded your music collection, you can play tunes on any Internet-connected device using the Cloud Player (although that's not yet available in the UK, but Amazon says "stay tuned"). So if you're on holiday, you'll still be able to annoy your other half with your hair metal playlist chirruping from your phone. Excellent.
Amazon has scheduled a press event for 6 September, with rumours abounding that it'll unveil the sequel to the Kindle Fire Android tablet. The Kindle Fire 2 is said to be thinner, lighter, and have a rear-facing camera, which was missing from the original (which still isn't available to us Brits). The screen could also be beefed up to 1,280x800 pixels, matching the Google Nexus 7's. The Nexus 7 has undercut the Kindle Fire, so Amazon could well want to see off the threat from the Big G.
It could even launch the Kindle Fire 2 here in the UK. Imagine.
Have you signed up for Cloud Drive? What do you make of it? Let me know in the comments, or on our Facebook page.
Update 28 August: Clarified availability of Cloud Player.