I didn't start until Goblet of FIre was released, but I am now a faithful fan. Each time a new one comes out I go back & start at the beginning- I haven't ordered the last one yet- it's in my cart at Amazon, BUT I did read about about the interview JK did Meredith on the today show. That's okay - I think it will be great. I plan to start the immersion process tonight & expect # 7 to be on my doorstep by the time I finish rereading 1-6!
My favorite part is that she as she aged the characters the story became more mature as well. It's really good stuff.

I must also add that when Psycycle path first handed me the Trek 5200 (Now known as old blue) to ride a bike for the first time in many many years he said- 'It's faster than Harry Potter's broom'.