As I understand things;
*Yes, they'll be updating their core books and settings.
*They'll release a free PDF conversion guide.
*Current edition (Deluxe Explorer's Edition) will still be fine, hence why they're releasing the conversion guide mentioned above.
From the previews they've shown they've changed skills and added so-called 'everyman skills', tweaked the chase rules, changed how ranged weapons work and added in some new conditions.