I've been working on a presentation on the accumulo sample, which will show off some of the accumulo-specific features. But when I ran it, I found very poor performance on some queries, and inconsistent results when I changed the user's authorizations.
Some queries like "three little pigs" ran with sub-second response times. Other queries such as "old man sea" would take as long as 8 minutes.
If I searched english-only articles, I would get more results than if I searched all the samples. Again, this only happens on some queries: the majority ran fine. "old man sea" would consistently show broken behavior.