The application is called "Ubuntu One Files" and it not only lets you access your Ubuntu One files but it also lets you instantly upload any photos you take to your Ubuntu One account. In fact, the first time you run it, a pop-up screen will ask you if you want to automatically upload existing photos or future photos to Ubuntu One:
The application also lets you upload new files and create new folders, rename, delete or publish your files. You can also share your files on Facebook, Twitter, Flickr and so on. For this, simply tap and hold on a file and the options window should pop up:
By default, Ubuntu One File lists all your existing Ubuntu One files but it doesn't automatically download them. To download them on your device you must click the files:
Ubuntu One Files is open source so if you want to check out the code, see its Launchpad page.
To install it, visit Ubuntu One Files on the Android Market or use the QR code below:
Since this is the first public release, expect to find bugs. You can report them @ Launchpad.
Note: in my test, authenticating with Ubuntu One through Opera failed so you may want to try this using a different browser (the stock browser worked just fine) - at least that was the case on my HTC Desire HD on which I've tested it.
News via Canonical blog