I know business objects and OBIEE BI tools, and have recently moved into the NoSQL(cassandra) space.
Great to hear theres a free jaspersoft cnnector
a) Whats the latest version of apache cassandra/datastax cassandra supported?
b) In Traditional BI there is a concept of a metadata layer - in jaspersoft for cassandra- is there a metadata layer, or do developers handcode the CQL behind EVERY report required by business?
You'll get a better reponse on the JasperServer forum (instead of the JasperAnalysis forum where this is posted). The front page of the Big Data Project links straight to it.
a) Cassandra 1.0
b) You write the parameterized CQL in a report definition. As the CQL JDBC driver improves, it should be possible to link Jaspersoft's metadata layer (Data Domains) to this. But it's not possible yet.
Refer to the Cassandra Connector documentation for more details.
Bonus question: "how can one publish the reports..."
Use JasperReports Server. It's downloadable from jasperforge.org or jaspersoft.com (Community Edition or Professional Edition respectively).