The much maligned demo, while useful, could use a breath of fresh air. This issue is to start collecting requirements about what people would like to see in a demo and what they don't like in the current one.
Ideas (not necessarily in order of importance):
1. More in-depth tutorial explaining indexing/searching
2. Multilingual support/demonstration
3. Better demonstration of querying capabilities: Spans, Phrases, Wildcards, Filters, sorting, etc.
4. Dealing with different content types and pointers to resources
5. Wiki use cases links – I think it would be cool to solicit people to contribute use cases to the docs.
6. Demonstration of contrib packages, esp. Highlighter
7. Performance issues/factors/tradeoffs. Lucene lessons learned and best practices
1. Hadoop + Lucene
2. Writing custom analyzers/filters/tokenizers
3. Changing Scoring
4. Payloads (when they are committed)
Please contribute what else you would like to see. I may be able to address some of these issues for my ApacheCon talk, but not all of them.