I still think that the film version was garbage at best because it seriously portraited Saruman as just a huge idiot while completely glossing over his hidden desires of the ring -a step which is practicaly necessary as Fellowship starts at a point were Saruman just starts his assembling of an army, whereas in the book, Isengard is already tainted and ready for war. Therefore the entire scene makes not one bit of sense, because the fact why Saruman acts as he acts is just ignored.
Well, I don't really think that the whole White Council plot was total garbage.
Actually, many people, as I have read throughout the Internet, liked it very much; some at the point of saying that it was one of the precious elements (very few) that 'saved' the Hobbit trilogy.
I personally agree with them, and, in my opinion, the White Council plot was the best part of this serie of films, and the one that I enjoyed the most (even though it is a secondary subplot in the whole Hobbit plot).
Not only was it great because we had the chance to see again on the screen really superb actors, but also because it was very interesting and impressive having a deep look at the events which involved mighty characters as the members of the White Council are; this subplot was arguably the element that connected the two trilogies the most.
But this doesn't mean, of course, that there wasn't any flaw in it either way.
Concerning Saruman, one could keep on talking about his role and the actions of the White Council for hours; I will just say that the portrayal of this subplot was more than satisfying, in my opinion, if we also consider that, according to the pure lore, the vigilance of the White Council, the investigation of Gandalf and the interest of Saruman for the One Ring involve centuries, and thus it would have been above the common cinematographic standards focusing too much on these characters and following strictly the lore (we are still talking about films).
Nonetheless, I believe that there are indeed a few deep and subtle (very subtle) hints of the interest of Saruman about the One Ring both in AUJ and BOTFA.
The fact that he strongly believes that Sauron and the One Ring have completely disappeared from the World could be indicative, or the fact that he knows a lot about the Rings of Power in general, showing an enigmatic interest (also, in the EE of AUJ, Gandalf and Saruman have a brief discussion about the Seven Rings of the Dwarves).
However DieWalküre's idea about a map special in DG could be a nice idea. What makes me uncertain about this is the fact, that the DG-map is more of Sauron's fortress from the war of the ring while the hobbit-DG is more his secret lair after his fall, which he choose to do his research at the last known place the ring once was.
It's true, Sauron hid in Dol Guldur to recover his powers, but it's also true that this place was already dreadful and dangerous; its poisonous influence had already started to corrupt deeply the environment of Mirkwood for a long time, forcing Thranduil to move his realm in the far North of these Woods.
Furthermore, we have to consider that Sauron himself was directly present in the fortress, and this raises the standards on another level.
