Holistically, Talent Management includes:
- Performance management
- Goal management
- Compensation management
- Recruiting
- Learning
- Succession planning
- Career development planning
- Onboarding
From a technical perspective, it depends on your SAP version. From ECC6 EhP4 succession planning is no longer part of E-Recruiting. Training & Development has been replaced by SAP Learning Solution (LSO) some time ago.
SAP's strategy is to use SuccessFactors HCM suite for talent management instead of SAP ERP HCM.