http://nerdgasmicblog.blogspot.com/2015/04/star-wars-battlefront-is-starting-to.html

a few things from the article.

1) No single player campaign. They will have missions that can be played solo or co op. You can play these missions over and over and over. So who needs a campaign?

2) No Galactic Conquest mode. Battlefront 2 had it.

3) 20 vs 20 is the maximum player cap. Even less in some modes.

4) No space battles or fighting in orbit. Battlefront 2 had it.

5) Game is launching with only 4 playable planets. Unknown how many maps per planet. Battlefront 2 had 16 planets and 33 total maps.

6) Only original Trilogy characters and units will be featured. No Clone Wars, or Wookies, or any of the fun stuff Battlefront 2 had.

7) The AT-AT's featured in the teasers are not player controlled and follow scripted paths across the battlefield. In fact no confirmation on any vehicles that will be playable yet. Battlefied 2 had 37 controllable vehicles and 15 controllable turrets.