I haven't actually watched the movie (Arceus that is), but this is what I got from Wikipedia:
"Meanwhile Team Rocket decide to steal some watermelons, only to come across a disguised Voltorb which sends them blasting off. Ash, Dawn and Brock continue their journey through Sinnoh, moving ever closer to their goals and with many more adventures still to come..."
Also, the new movie looks good, but I haven't actually seen a Pokemon movie since the third one.
Also, the G.S. ball idea should DEFINITELY be implemented, I've been wondering about that forever.