bigtable vs cassandra vs simpledb vs dynamo vs couchdb vs hypertable vs riak vs hbase, what do they have in common?

Question

Sorry if this question is somewhat subjective. I am new to \'could store\', \'distributed store\' or some concepts like this. I really wonder what do they have in common and wan

Answer 1

Good overview of the nosql world: http://www.vineetgupta.com/2010/01/nosql-databases-part-1-landscape/