Microsoft has just released information about the next version of Sharepoint, Sharepoint 2013 or Sharepoint 15. Microsoft released a preliminary SDK called SharePoint 15 Technical Preview Managed Object Model Software Development Kit, follow the link to download. 

SharePoint 15 Technical Preview Interoperability API Documentation

If your download does not start after 30 seconds, click here: Start download

Instructions

To install the documentation:
  1. Download the documentation by clicking the above Download link, and then save the file locally.
  2. Unzip the file, and then copy the SP15InteropAPI.chm locally.
IMPORTANT: On computers that have security update 896358 installed, you cannot open Compiled Help Module (.chm) files that you download. For more information, see the Microsoft Support Web site.

To use the documentation:
After you save the file locally, you can view its contents by using one of the following methods.

Method 1

  1. Open the SP15InteropAPI.chm file.
  2. In the Open File-Security Warning dialog box that appears, clear the Always ask before opening this file check box.
  3. Choose Open.

Method 2

  1. Right-click the .chm file, and then choose Properties.
  2. Choose Unblock.
  3. Double-click the .chm file to open the file.


Removal of this download

There is no removal feature for this download. You must manually delete the .chm file.

Source: www.sharepoint247.com