I love the book. I was given It as a birthday present when I was 11 - about a year before the TV movie came out. The first time I read the book, I read It in a weekend.
Even now, nearly 25 year later, I still read it a few times a year, and I still have that same battered well-worn copy from when I was 11.
The novel was so much better than the TV movie. I've seen the TV movie a few times, but there was just so much cut from the book that some of the things in the movie don't actually make sense unless you've read the book.
There were also a few inconsequential things that were altered around for some unknown reason. For example. right at the start of the movie the child who is killed was a little girl but in the book that exact same child was a little boy (and the murder doesn't happen at the start of the book, Georgie's murder happens at the start of the book). In the book the timespan between them as kids and them as adults was 26 years but in the movie it was changed 30 years. In the book, Beverly has a mum and a dad but in the movie she only has a dad. It never really made sense to me to make changes like these.
The remake actually stands an excellent chance of being far better than the original. They would have to get it seriously wrong for me to have my usual opinion of the original being better than the modern day remakes.