Heehee. This book sucked me in from the get-go (which was around midnight, stupid me), and kept me intrigued and on the edge of my seat (figuratively, anyway...I suppose "edge of my bed" would be more accurate) until I finished the last page (at 4 something in the morning, stupider me). It was a library book, but luckily for me, my sister owns the second book so the next day after I dragged myself out of bed (also luckily for me, I had nothing going on that day) I borrowed it and read it straight through, as well. Alas, my sister doesn't have the third one, so I have to wait to get it from the library.
Some Things I loved about it:
1. The characters. They were all interesting in their own ways, with their own secrets and personalities that drew me into the story. I consider character to be more important to a story than plot (that is, I'm more forgiving of a poor plot than poor characters), and in The Summoning, Chloe was intriguing from the start, and the other characters were, too, as they were introduced and then developed more in Chloe's eyes. Plus, I thought the interactions--friendships and non-friendships, etc--between them was realistic and believable.
2. The plot. Even though not much actually happens in this book--Chloe's stuck in a group home for crazy teens most of the book--it feels like nonstop action, and the climax is...well, climactic, to say the least. :) It leaves you hanging, which can be considered either good or bad. Good, for me, since I waited till all the books in the series were out to read them.
3. The hint of romance--it was sweet, and, I thought, age-appropriate and believable.
On the whole, it was very gripping and entertaining and left me eager for more.