I have been scouring the Adobe website and even contacted customer service for a list of all the changes made from Livecycle Designer ES2 to ES3 and then ES3 to ES4 with no luck. It seems like something basic that would be available. I am currently using ES2 and need to know if anything was changed or added to ES3 and then ES4 to see if it is worth the cost of upgrading. I do not use any of the other components of Livecycle and pretty much all the information on the Adobe website always goes back to those programs or how Designer works with those programs and it does not apply to me.
It is frustrating because it seems like Designer is an neglected stepchild of the ES Suite.