I'll post my comments in this post since the first was massive
1. Newton practically confirmed
2. There are tons of little things I like, such as being able to delete games with a Gamerscore of 0 and disabling invites.
3. Games will be able to stream off the hard drive if there is one. I'd expect games like GTA to get updates soon.
4. Still no support for external hard drives, except for transferring new types of media files...