Techn9ne of rumorpress.net has said through a friend that the Bulls target while trading up is James Johnson or Gerald Henderson. He hasn't posted it on his official blog yet, but his rumor was reported on bullspodcasters.com as well as realgm.com.
I have no problem believing this rumor given that Johnson would be the first guy I would trade up to get, and Henderson would be someone else I'd be very interested in if I moved up in the draft.
The trade would likely be the frequently rumored move with the Nets packaging #16 and #26 for #11 overall. While mock drafts have had Johnson falling, from scouting the players, it's hard for me to imagine how Johnson lasts to pick #16.
I'm highly in favor of moving up for Johnson if that's what it takes to ensure the Bulls land him.