This would allow for example to write the following POJO:

public class LuceneBlogIndexer implements BlogIndexer {
  @OnEvent(event = KeywordSearchResult.class)
  public void indexKeywordResults(KeywordSearchResult results) throws RemoteException {
    for (BlogEntry blogEntry : results) {
      index(blogEntry);
    }
  }

  public void index(BlogEntry blogEntry) throws RemoteException {
    System.out.printf("Should index entry %s [%s]\n", blogEntry.getTitle(), blogEntry.getPermalink());
  }
}

where the indexKeywordResults() method would be called automatically when a KeywordSearchResult entry is written into space and index(BlogEntry) would be part of the service interface for synchronous calls.