You can try Achilles : https://github.com/doanduyhai/achilles, an JPA compliant Entity Manager for Cassandra
Right now there is a complete implementation using Thrift API via Hector.
The CQL3 implementation using Datastax Java Driver is in progress. A beta version will be available in few months (July-August 2013)
CQL3 is great but it's still too low level because you need to extract the data yourself from the ResultSet. It's like coming back to the time when only JDBC Template was available.
Achilles is there to fill the gap.