Currently the maximum identifier length of tables, columns, packages, functions, etc. is limited to 30 characters.
This should be increased to 60, 90 or more characters, allowing for more flexibility and readability in object naming.
Realize this has the potential to break a lot of old applications, so it should probably be explicitly enabled by a configuration parameter, just like the "32K varchars in tables" option that was introduced in 12c.
Update: Oracle Database 12c R2 provides identifiers up to 128 bytes. For more information see the 12.2 New Features Guide.