Today the W3C advanced the spec for CSS Backgrounds and Borders Module Level 3 to Last Call status. This means that the WG is happy with the standard, and officially invites all web developers to test and critique the specification (though in reality the back-and-forth has been going on for some time).
Previous drafts separated CSS3 Backgrounds and CSS3 Border; the current working draft acknowledges, correctly I think, that backgrounds and borders serve sufficiently linked styling purposes that developing the two specs separately (as distinct CSS3 modules) is likely to introduce more noise than ideal. The property index unifies the two concerns, and presents properties and permitted values concisely.
W3C's summary of what's new in CSS3 backgrounds and borders:
The main extensions compared to level 2 are borders consisting of images, boxes with multiple backgrounds, boxes with rounded corners and boxes with shadows.