Templates.com has just compiled a list of free User Interface (UI) kits for designers to download. This is not only a superb resource, it gives a good overview of the state of UI design in 2012.
Gone are all the Apple-inspired glossy surfaces. Instead they have been replaced by subtle dropshadows and pastel shades. Two-colour schemes seem very popular, and many of the examples here sit on faintly patterned backgrounds, giving a sort of vintage look.