I was a HUGE fan of Eleanor and Park, so, picked this one up. It was mostly an enjoyable read, though, Rainbow's penchant for writing nuanced, realistic characters (and in this case, so realistic they were mildly annoying/unlikable) was really the hiccup for me in Fangirl. In some cases' I considered DNFing because I just wasn't super into the main characters. Any of them. 
 As a former fangirl, and reader of fic, I really, REALLY appreciated the fandom/fic culture references in this novel, almost more than the story itself. It was like a lovenote to all us fic-readers. 
 I'd say that the story was decent, the characters where meh (but only in their painfully realistic-ness), and the fic references were a treat for me.