September 30th is the publication date of the new Report:
http://www.ipcc.ch/
The Fifth Assessment Report (AR5) will provide an update of knowledge on the scientific, technical and socio-economic aspects of climate change. It will be composed of three working group reports and a Synthesis Report (SYR). The outline and content can be found in the AR5 reference document and SYR Scoping document.
The Working Group (WG) Reports and Synthesis Report will be completed in 2013/2014:
WG I: The Physical Science Basis
23-26 September 2013, Stockholm, Sweden
WG II: Impacts, Adaptation and Vulnerability
25-29 March 2014, Yokohama, Japan
WG III: Mitigation of Climate Change
7-11 April 2014, Berlin, Germany
https://www.ipcc-wg1.unibe.ch/
http://www.climatechange2013.org/
The Final Draft of the Working Group I contribution to the IPCC Fifth Assessment Report will be available here on 30 September