No, I haven't bought this book yet and haven't read the above posts but I know what the ending should be:

Harry will lose his magical powers in the final climatic battle, and only have vague memories of his alternative life. However, that will be sufficient to inspire him to begin writing a fantasy series which will be a spectacular success, focused on the growth of a young lad who has latent magical powers. Unfortunately he will die at a relatively young age from an infected bruised elbow incured from signing hundreds of thousands of books.

Beware, take care! Success can have mortal consequences.

Charley Noble