I couldn't find a thread yet so I'm creating one as I'm really excited about this.
There are reportedly going to be 5 seasons. Almost 250M paid for the franchise so the season budgets should be immense (some are estimating 150M per season!). Peter Jackson may be involved as executive producer. Amazon said that the project will “explore new storylines preceding J.R.R. Tolkien’s The Fellowship of the Ring,” in addition to a potential spinoff series.
I grew up reading the Hobbit and Lord of the Rings (even the Silmarillion) . There is truly no limit to the stories and spin offs that are possible. My hope is that they just make a good show that I doesn't try to replace or push out GoT and Star Wars.