Since we are discussing the evolution of Bruce's look throughout the series, I thought I might contribute my impressions on the Bruce Wayne disguise, specifically Bruce's business suits. I know kvz5 and others have mentioned that they think Bruce's suits in TDKR look ill-fitted, but I would argue that they are not. They are simply the traditional baggy Armani cut, which is considered rather classic, but which is currently out of fashion. Bruce's suits in The Dark Knight had the same cut. (see below) They are still well-cut, expensive clothes that you will see many men in his social strata wearing because good suits are supposed to last a long-time.
Hemming mentioned that they kept Bruce in Armani for character reasons and I think there is significance in the style of the suits. They are perfectly suited (pun not intended) for an eccentric billionaire who is stuck in time. Bruce's suits haven't changed with fashion because he hasn't. Moreover, the traditional baggy Armani cut is visually associated with 1980s Wall Street, which is very fitting given the film's apparent social themes. Finally, whether intentional or not, the looser cut of Bruce's suits do a great job of hiding his physique. If Bruce was dressed in very slim suits like Daniel Craig will be in Skyfall, it would be rather obvious that he is a very well-built man and people might wonder why someone who spends his life partying and chasing women got in such great shape.
A Quick Visual History of Bruce's Suits:
Batman Begins
As you can see, Bruce began the series wearing relaxed cut Italian suits. I can't find any mention of the brand. I don't think they are Armani because in recent quotes about TDKR, Hemming would probably have said "we kept him in Armani like in the past films" instead of "the last film" singular.
Bruce's suits appear to be Brioni. They are remarkably similar to the Brioni suits Hemming dressed Pierce Brosnan as James Bond a couple years prior.
The Dark Knight
Bale wears Armani suits cut in the house's traditional soft, relaxed style.
The Dark Knight Rises
Same as above except Bruce seems to have made a few concessions to current trends. He is now wearing flat front trousers and his jackets are two-button fronts instead of three. (seems he took Lucius' comments in TDK to heart)