A new shared-use cycleway has been built at Arundel station. The new route passes under the railway bridge, on the north side of the railway, and along the eastern side of the A27 towards Arundel.
It is unknown which organisation devised and funded this bit of infrastructure - but it is welcome. It means that people on foot and on cycles can get from the station into Arundel without having to risk the A27 and the roundabout into Arundel.
The closest we have to official news on this is via this blog post, written by Paul Dendle who is an Arun District Councillor:
http://www.pauldendle.org/2015/04/arundel-station-cycle-path-coming.html