Conclusion
- Annotations can be treated as RDF metadata
- The reuse of current Web standards makes the implementation relatively
easy
- Open infrastructure
- RDF schema for defining annotation properties
- XPointer for associating annotations to any XML document
- XLink for presentation
- HTTP for data exchanges
- Easy to extend (discussion threads, WAI
evaluation, ...)
- Client independent
- Some obstacles remain
Scalability issues
Robust annotations
...