Just refreshing my memory here, but this blog post [1] is what kept me away from secondary indexes and explains why I need something more from Cassandra. Especially the section on "The Good: Secondary Indexes", I actually have some data that is stored by timestamp, that was, as I recall, the biggest turn-off on them.

Has the state of affairs advanced since a year ago? Would love to hear it has!

[1] http://brianoneill.blogspot.com/2012/03/cassandra-indexing-g...