The rules are a lot different than 3rd edition. The changes between 3.0 and 3.5 are almost trivial comparing 3.5 to 4th edition. Even comparing it to Star Wars Saga, SWS is a lot closer to 3.5/d20 Modern than 4th edition. Speaking of Saga, that game has been a blast so far.
I played a couple pre-made adventures. It's fun... but more fun? No. Faster combat? No. Faster character creation? It took us over 3 hours to make a 9th level dwarf fighter... so no, not faster. Some of the rules are also counter-intuitive. AC/Reflex is the best of Dex or Int? Um, okay. Fortitude is best of Str or Con? What?? Open Lock DCs, 20 "heroic", 30 "paragon", 35 "epic"... what the hell does that even mean? I get I'm going against harder locks at epic level, but explain it the way you did in 3.5, show DCs for poor locks, average locks, good locks, etc. Not some metagame "epic lock" DC.
So its a fun game, but so far I couldn't say its a better game. Some things are better, but some things are worse. Supposedly it was going to be more "balanced" too, but clerics and wizards can still be gods (literally) at high levels. They always were more powerful than fighters, they still are. Nuff said.