tnuge,
Oracle replication should be addressed by your companies needs and or hardware software limitation.
Take a look at this pdf or html from Oracle web site.
http://download-east.oracle.com/docs/cd/B14117_01/server.101/b10732/toc.htm
Using any replication tool requires hardware and a Good System Administrator that is knowledgeable in his or her field.
Cloning or BCV's replicate data as a 1 to 1 copy, brake the clone and mount it on a different mount, start the database (not recovery needed) and you now have an perfect replica of your production database.
SNAP or Snaps replicate data at a block level and only keep track of the changes, in the case of a database snap the data base must be copied and recovered and in some cases logs need to be applied.
Data pump ships with oracle
http://builder.com.com/5100-6388_14-5800445.html
RAC is super expensive, I know what the concept is but have not worked with it.
JD