Thanks for the link, it will be useful if I try to make a case for cassandra vs redis. Other questions: how robust are the clients (especially for php), and are you aware of any performance/scaling comparisons between cassandra and redis?
the clients are thrift, and the commonly used ones (java, python, ruby, C++, php), are robust, although the thrift devs are slow to apply patches sometimes (all the php users I know have applied http://issues.apache.org/jira/browse/THRIFT-347).
redis is faster per node, but does not scale, there is not much to compare. :)
True, but we're working on that (and we're very responsive on IRC and mailing lists).
> not enough big projects are using it
I don't think that's true anymore; Digg, Facebook, Rackspace, Twitter, Mahalo, Ooyala, SimpleGeo, WebEx, and others are using Cassandra: http://n2.nabble.com/Cassandra-users-survey-td4040068.html