blender build viewport rotation question...

Does anyone know how to make the viewport rotate into a different view? I have an older Graphicall build of blender, and when you switch from say top view to side veiw it rotates into place. This gives a better idea of what is going on while modelling.
How is this enabled? Is it build specific or a user setting? Please help.
I would like to update my build but cant find this feature on other builds.
Thanks,
Don.

In my official release it’s in User Preferences -> View and Controls. Set “Smooth View” to several hundred milliseconds.

Thats it! Thanks for your quick response. Happy Holidays.
Don.