Selecting your OpenUI theme can be done through the usual mechanism by setting it in the User Preferences – Behavior view. As added feature you can now globally set it on object manager level too. Under many circumstances this makes sense because often customers will not give their end users the flexibility to select another theme.
Another alternative would be to default a certain theme using Manifest Administration, which is also a new capability in IP14. See @lex post about Themes and Manifests in IP14 to get a grip on this functionality.
And then there is a third approach: a new component parameter “DefaultNavigation” has been introduced as part of IP14. It it seeded with “NAVIGATION_SIDE”.
Values can be any of the Language Independant Code values “NAVIGATION_SIDE”, “NAVIGATION_TAB” and “NAVIGATION_TAB” (or a custom theme you added of course). These LOV values belong to Type = “NavCtrlPR”
Next it would be nice if we could also default the transition at the object manager level 😉