I hope so! For the most part I thought the summoning system in BD was improved over DD, except for the fact that each doll was pretty much obsolete by the next act. You more or less had to start investing in a new doll in each act, and the points that went to the old one felt a bit wasted. With some tweaking of the skills this could easily be avoided.
Along the same lines, I hope we get a chance to add some NPC's to our party; not necessarily for the duration of the game (would be kind of hard for them to follow in you in dragon form - unless they rode you

), but at least for some major battles or quests it would be nice to have some companions to control/fight alongside.