The yum list updates command will show you a list of software that would be updated. The command yum update will display all software updates before you press Y to continue. There are usually a vast number of application and kernel patches. What you need to look out for highly depends on what application you use.
However, if you Oracle Linux and Oracle products, and not RHEL or CentOS, you can probably spare yourself a lot of effort. Oracle Linux and the Oracle UEK kernel goes through extensive testing by Oracle to assure it works well with Oracle products. This is mentioned in many Oracle white papers, and I think it is the best guarantee you can get, beside updating a test system and perform tests with your specific installation.