What skill sets are required to be a SAP Netweaver Portal Developer?

To be a fully qualified SAP Netweaver Developer, you need the following skill sets to do the most common development project: (At present, SAP Netweaver Portal can be developed using two different skill sets : Java + WebDynpro technology OR ABAP + Webdynpro - I will only cover the first case)

1) Java / J2EE + Web Development skills
2) SAP Netweaver Framework Concepts
3) SAP Portal Framework, i.e. iView development and other content development skills. (Will cover in depth in the future)
4) Development Tools: SAP Netweaver Developer Studio (Eclipse based platform) +Java Development Infrastruture
5) Special development areas, i.e. Knowledge Management & Collaboration, Business Intelligence, Exchange Infrastruture and etc.
6) Some SAP backend systems knowledge, like R/3 (most common - HR and Logistic) , BW, CRM and etc.
7) Some functional knowledge (business), i.e. Human Resource Management (most common - Employee Self Service and Manager Self Service), Customer Relationship Management and etc.
(Usually, a developer will only focus in one or two functional area.)

The first 4 items will qualify you as a SAP Developer. To be a good or high demand one, you have to fulfill all of them.