Actually, I kinda thought that if there was a Smallville Barbara Gordon (or in this case another kind of Smallville Barbara Gordon), that she she wouldn't be Nightwing, nor even Batgirl either, but Oracle. That way, as Batman and Superman butt heads, so will her and Chloe at first. Of course, Bats and Supes become partners, and so will the gals as well.
Hey BTW, no one has asked this yet: what will Smallville Batman have in his arsenal? Will he have the Batmobile or somethign else (maybe he changes in the Wayne sportscar to draw rumors of what Bruce might be doing, then goes out into the night like Year One, or because its a normal car; like the old serials). Batarang? What about the Batcave? Or will he have something that he did have in the comics, but it was well known outside of the comic community, and will be treated as the main elements for this universe?