The Forbidden Library, by Django Wexler (Penguin, April 2014, middle grade) -- a review in three acts.
Act 1: In which we meet Alice, and the Library
Alice, who quickly becomes an orphan once she
a. realizes she's the heroine of a middle grade fantasy
b. loses her father to a mysterious boat accident in which a nasty insect fairy person might have had a hand
is taken in by her "kindly" uncle who has
a. a big house
b. a big house with really strange and creepy staff of two and no clear reason for putting Alice in a maid's room at the top of the house
c. a Forbidden Library
and Alice of course enters the Forbidden Library and starts becoming embroiled in its secrets.
Act 2: In which there are magical secrets revealed
Setting: a library with lots of mysterious bookish passages, nooks, etc, as well as (more unusually) places where the ambiance and environment contained within particular books leaks out, causing physical ramifications.
In the library, Alice meets
a. a cat
b. a boy
both of whom strike up conversations with her,
And finds that
a. it is possible to read oneself inside certain books, after inadvertently doing so and almost being killed by the cute little deadly killers trapped inside.
b. She's really good at reading herself into books, and now has psychic control over the whole host of cute little deadly creatures (this comes in useful in Act 3)
[The book is illustrated, but the picture of these little creatures is the only one I noticed because the cuteness is just too cute. Does anyone else read so fast you can't remember if a book was illustrated or not?]
Act 3--In which we learn that not everyone can be trusted and there were lots of things people weren't telling Alice
Turns out Alice is being used to do something magical that might have ramifications and there is Potentially Fatal Adventure involving the denizen of a very dangerous book indeed....
It's a perfectly fine fantasy adventure, with a nicely detailed and intricate plot and setting ( although I expected more actual bibliophilia). Not a huge amount of emotional depth, but that's not a necessary prerequisite for middle grade reading enjoyment, and there was enough actual rational thought and sincere feeling on Alice's part to make her more than a place-holder. She also gets points for pluck.
So basically, I enjoyed reading it just fine, can easily imagine lots of 11 year olds enjoying it, don't particularly want to urge it on adult readers of middle grade fantasy in a Read This Now because My God it is Brilliant way, but wouldn't want to dissuade anyone from reading it either. I will be reading the sequel; it ends at a good ending place but clearly there needs to be more.
Those who like The Books of Elsewhere series, by Jacqueline West (another trapped by magic story, though in paintings, not books, and another one with talking cats) might well enjoy this too.
Here is the UK cover, which I personally prefer; the US cover makes me think of Poltergeist.