As an avid fantasy reader, catagorizing His Dark Materials and Harry Potter in the same level is just not right.
Harry Potter is a vividly imagined fantasy world, yes, and epic, of course, but that's all it us. A good read. I have great respect for JK Rowling, but I would never in my lifetime place it in the same catagory as His Dark Materials. Here's why.
Yes, Philip Pullman was inspired by a few poems and writings. But unlike the Harry Potter series, HDM focuses not only on the story of its characters, but everything. Pullman came up with some of the most orignal ideas ever in terms of fictional writing. Examples of this would be daemons. Pullman has stated that while looking at DaVinci's mysterious painting "Lady with an Ermine", he saw the inderrent stare of the young girl. Then he saw the face of her creature, which betrayed what he thought would be her true sentiments. This is how he came up with the idea of a daemon; the part of your soul and personality that can exist outside of one's body.
Harry Potter deals with good vs. evil. Harry is undoubtedly good, while Voldemort is characteristically evil. Its the all too common and predictable clash of light vs dark. His Dark Materials deals with Humanity. How we all have qualities of good and bad in us, but our actions, rather than are beings, can be defined so. He examines the complexity of character as it is, not as it should be. He has put physical characteristics to intangible things such as innocence and knowledge, and has broken the barrier in childrens books, because this is a trilogy that should and is being read by every age group. The amazing thing is that it means something different to a reader depending on their age or maturity. For a child, its simply a cool story about bears and witches and angels, but to someone older it means so much more.
While I did enjoy reading Harry Potter, I wouldn't classify it in my top ten. HDM is undoubtedly at the very top of my list, and I completely agree with you. Although the film is nothing when compared to the book, I have to admit that I do enjoy watching it for the sake of visual reference.
And yes, its heartbreaking that it had to end.
Finally, when I first started reading the Northern Lights/Golden Compass, I quit as well. It took me about 6 chapters into the book to put the book down. But then, one year later, I picked it up again, and obviously my sentiments about it are different now.
That's what I feel is the difference between HDM and Harry Potter: His Dark Materials has the power of forcing you to rethink your ideals and what could have seemed most stable beliefs. Harry Potter is a good read, but HDM pushes boundries and is simply a darn good trilogy, imo, the best.