I've been looking forward (and I hope many others as well) to have the XSD 1.1 language to become a W3C recommendation (REC). XSD 1.1 did become a REC on 5th April 2012. This was a big big wait for the XSD community! But finally this has come so. The previous XSD standard (XSD 1.0 2nd edition) dates back to 2004.
XSD 1.1 implementations: There seems to be currently two XSD 1.1 implementations, which are Xerces and Saxon. Xerces is a project from Apache Software Foundation's XML activity, and Saxon is a product set from Saxonica (via Michael Kay). Both of these implementations pass near to 100% of the W3C XSD 1.1 test suite, so these tools are reliable implementations of the XSD 1.1 standard.
For the interest of readers (for those not aware), following are the feature change list (these are non-normative details, but are fairly complete. for the complete list of changes within XSD 1.1 wrt the XSD 1.0 language, you'll have to read the whole of XSD 1.1 language) that is within the XSD 1.1 language:
XSD 1.1 Structures specification: http://www.w3.org/TR/xmlschema11-1/#changes
XSD 1.1 Datatypes specification: http://www.w3.org/TR/xmlschema11-2/#changes
Wishing a happy reading, to the XSD folks (and to the wider XML community) of the new XSD 1.1 specification, and trying out the available implementations :)