I've only had a chance to glance over it so far, but here's a few observations:
The skills are now tied to certain abilities. It says the DM can use other abilities instead, but it's generally assumed that you will usually use the specified ability for that skill.
The pregen Fighter is an archer this time, which was unexpected but cool. I'm not sure I like how Precise Shot works with the fighter's combat superiority, though. We'll see how it works in play.
I'm glad that they put the spells on the character sheets this time.
It seems that the + ability modifier damage bonus has been removed from all spells except for cantrips and orisons. Not at all happy about that change.
Strangely, alot of the spells just have a flat +3 or +4 bonus instead of +magic ability modifier. At first I thought that this was just a convenience on the character sheets, but it's written the exact same way in the general spell rules. I'm hoping that this is a typo, as it would be silly, IMO, for all casters to cast spells with the same strength regardless of their ability scores.
The spells are still written in the same format as before, though the spell descriptions seem a bit more clear. Detect magic in particular is much more clear on what exactly it does and does not do.
Magic Missile no longer scales. It still has crappy damage (1d4+1) and auto-hits. Bleh. I'd much rather roll to hit and be able to crit, and have it deal decent damage, than have it auto-hit, personally.
Ray of frost does damage now and drops the target's speed by 10 ft. Much better than the last version.
Charm Person has been changed a bit. It now goes by the target's maximum hp rather than current hp, so you can no longer beat up someone until you can charm them. If you have less than 25 max hp, you don't get a saving throw at all though. Considering the reduction in hp across the board, that raises a red flag.
Shocking Grasp no longer gives advantage against metal-wearing targets, but prevents the target from taking reactions until its next turn. Cool.