Start your education by reading these notes:
Note 359145.1 - Impact and overview of 2007 USA daylight saving changes on the Oracle database.
Note 402742.1 - USA 2007 DST Changes: Frequently Asked Questions for Oracle RDBMS. Probably the most beneficial of all the overview documents.
Note 397281.1 - USA 2007 Daylight Saving Time (DST) Compliance for Oracle Server Technologies Products.
Generic time zone information:
Note 357056.1 - Impact of changes to daylight saving time (DST) rules on the Oracle database.
Note 340512.1 - Timestamps & time zones - Frequently Asked Questions.
Note 396906.1 - Patches to Update the Time Zone Transition Rules.
Note 412160.1 - Updated Time Zones in Oracle Time Zone File patches.
Installing and using the utltzuv2.sql script:
Note 406410.1 - Dealing with existing Database time zone use when updating Oracle TZ-files.
Note 396670.1 - Usage of utltzuv2.sql before updating time zone files in Oracle 9.
Note 396671.1 - Usage of utltzuv2.sql before updating time zone files in Oracle 10.
Note 397013.1 - Advanced use of utltzuv2.sql.
Note 402614.1 - Time Zone Data in the Data Dictionary During a Time Zone File Update.
Note 399832.1 - Workarounds when utltzuv2.sql patches are not available for your patchset.
Applying the time zone file patch:
Note 359145.1 - Impact of 2007 USA daylight saving changes on the Oracle database.
Note 396387.1 - Workarounds when Database time zone patches are not available for your patchset.
Note 396426.1 - Effects on client and middle-tier of applying time zone patches on the Oracle Database.
Note 402316.1 - Database Time Zone Patching Strategy in the Enterprise.
Platform specific information for those platforms with some special patching issues:
Note 406196.1 - VMS: DST 2007: Information for OpenVMS platforms.
JVM issues:
Note 359145.1 - Impact of 2007 USA daylight saving changes on the Oracle database.
Note 397770.1 - How to check if Oracle JVM is installed in the Database.
Note:276554.1 - How to Reload the JVM in 10.1.0.X and 10.2.0.X.
Note:209870.1 - How to Reload the JVM in 9.2.0.X.
Oracle Applications:
Note 403659.1 2007 - Daylight Saving Time Changes For Oracle Applications.
Note:403311.1 -Impact of U.S. 2007 Timezone Changes on Oracle E-Business Suite, Release 11i Environments.
Grid Control Issues:
Note:401834.1 - EM Agent will not start - due to a Daylight Savings change - (Workaround). Explains why it is impacted, how to fix it and the workaround.