Hi Rohit,
The documentation for CUCM and IM&P 10.x is merged. As per the install guide for CUCM
When you install Unified Communications Manager, the installation wizard prompts you to specify whether the node you are installing is the first node in the cluster. The first Unified Communications Manager node that you install becomes the publisher node, because it publishes the voice and video database to the other Unified Communications Manager nodes in the cluster. All subsequent nodes in the cluster are called subscriber nodes. Each subscriber node must be associated with the publisher node. You must set up all subscriber nodes in the system topology on the publisher node before you install the software on the subscriber nodes.
When you install IM and Presence nodes, the first node that you install functions as the server for the IM and Presence database. Because this node publishes the database for all of the IM and Presence nodes in the cluster, it is referred to as the IM and Presence database publisher; however, you must install this and all other IM and Presence nodes as subscribers of the Unified Communications Manager publisher node. As with other subscriber nodes, you must add these in the system topology before you install the software.
Also,
About the IM and Presence Service
IM and Presence, which is a service of Cisco Unified Communications Manager, provides native standards-based dual-protocol enterprise instant messaging (IM) and network-based availability as part of Cisco Unified Communications. This secure, scalable, and easy-to-manage service offers users feature-rich communications capabilities both within and external to the enterprise.
http://www.cisco.com/c/en/us/td/docs/voice_ip_comm/cucm/install/10_0_1/CUCM_BK_I95AD2FE_00_installing-cucm-100/CUCM_BK_I95AD2FE_00_installing-cucm-100_chapter_01.html
If there are any queries you can let us know.
Manish
