I think people are considering this with assumptions about the character based on how they expect her to be portrayed and the role they think she'll play in the film. I don't want to play coy, but I am aware of enough to say I think people will be surprised -- in a good way, but still surprised -- at the arc of this character and the reasons behind Mr. Nolan picking her.
He has thus far done excellent at knowing exactly the right people for these roles, because unlike us, he knows the details and how these characters will take shape on film. We, on the other hand, react based on the character we see in our heads, and our impression of this or that actor from whatever of their roles we've seen so far. We have no idea what elements of their personality and prior performances might precisely reflect elements Nolan is seeking for the Catwoman in HIS film, not the one in our personal vision of her that resides in our unique view of her in our minds.
In considering what "people think" about her casting, I assume (as opposed to a survey or poll attempt) that we are to explain how the public in general has reacted to this news.
I happen to be particularly well qualified to answer that, because I help run a site for fans and am directly aware of online discussion and speculation etc among the broad fan community, polling of fans and the public at large, and overall seeming reaction thus far. And while there is that segment of fans who dislike the casting because only their personal preference of casting for their own personal singular view of the character would ever be enough to make them happy, by and large the reaction has been very positive. Hathaway was long on the short-list of most-mentioned actors for the role among fans' short-lists, she was on the short-list of best options of many sites and critics, and the broad sentiment has been favorable.
Regarding the concerns about her being unseasoned, she has in fact amassed an impressive resume with work in many different genres and alongside many top-rated performers, she was nominated for an Oscar for Rachel Getting Married (whatever one thinks of it, she was nominated by many different groups that are prestigious and which represent performers and critics etc, people learned and respected in their fields, so it's as relevant as what we here or people elsewhere think, and so relevant to mention in a question asking for opinion in the first place), and is well-respected among her peers and the public in general.
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