The new features of Nexus Professional 1.4 include: New Repository Window
- Better control of redeployment for hosted repositories
- Provides a WebDAV endpoint for publishing a web site
- Support for staging rulesets
- Staging plugin now accepts artifact bundle uploads
- More intuitive staging plugin UI
- Repository summary panel
- Security improvements
- Integration with Atlassian Crowd
- Automated Nexus Error Reporting
Sonatype produces Nexus Professional as its premium commercial edition, while Nexus is the free edition. Both products are open source.
Nexus claims to have the smallest memory footprint of all Repository Managers (28mb vs 128mb). Nexus uses the file system with Lucene so no database is required. Nexus also uses Restlet, enabling full REST APIs. Full integration with Eclipse using m2eclipse is another core feature of Nexus.
To get started with Nexus, you can watch an introduction video.