New applications that have MDS will be compatible with future S60 releases and S60 SDK versions. Notice, that applications that have MDS are not backwards compatible with S60 5th Edition SDK.
Applications that use current S60 SDK APIs for file and drive handling will continue to work also with future S60 releases and S60 SDK versions. However, they may have some functional limitations, such as not having access to all user-visible drives available in a device.