In the last few days I have made several tests with SPS2013 and Office Web Apps 2013.
For the deployment and configuration I have used the following two articles:
- http://technet.microsoft.com/en-us/library/jj219455.aspx Deploy Office Web Apps Server
- http://technet.microsoft.com/en-us/library/ff431687.aspx Configure SharePoint 2013 to use Office Web Apps