XQuery 1.1 Draft
A working draft for a 1.1 revision to XQuery went up earlier this week. The changes from XQuery 1.0 (which was finished just last year) to XQuery 1.1 appear to be small. There are two additional operators for grouping and windowing over a data stream. The group operator is fairly standard while the window operator is a bit more unusual. Applying a window controls what it means to draw a sequence of consecutive items from the stream.
You can get the complete specification from the W3C site.