The major ETL (Extract, Transform, Load) tool vendors in the market include IBM with Cognos Data Manager, Informatica PowerCenter, and SAP BusinessObjects Data Services. These platforms provide comprehensive capabilities for data integration from source systems, transformation logic implementation, and loading into target data warehouses or data marts. Each has strengths in different areas like IBM's enterprise integration, Informatica's market-leading position, and SAP's integration with BusinessObjects BI tools.