While the full fact sheet for MLB 10: The Show has yet to be released most of the new features and additions have already been unveiled through the previews and cover announcement press release. Certainly there will be numerous improvements made to various areas of the game however the items that will be heavily marketed are already out there.
That belief is essentially confirmed given the back of the retail box displays only those new features which have already been discussed. Based on the poll from yesterday nearly 80% of people are content with the information on MLB 10 thus far. Continue on to view the full back of box image.