They were renamed between 0.3 and 0.4.  They are the same thing.
See https://issues.apache.org/jira/browse/CASSANDRA-271

Michael

On Fri, Sep 25, 2009 at 2:58 PM, Joe Van Dyk <joe@fixieconsulting.com> wrote:
Hi,

In some storage.conf's, I see <Tables> and in others I see <Keyspaces>.

Are they the same thing?

--
Joe Van Dyk
http://fixieconsulting.com