Interesting, most of the DBA scripts are available in single place, very useful one.

http://www.oracle-base.com/dba/DBACategories.php

New features are in one place like Virtual Column, assigning next value of sequence in assignment statement instead of select..dual, scheduling job in another server from oracle server, having more than one same type of trigger with follows option. Check the above URL for more information.

Prior to 11g, it was only possible to create triggers in the enabled state, then subsequently disable them. Now they can be explicitly enabled or disabled at creation time, with the enabled state as the default.