Well, I'm about 20 hours in, I might as well write up my thoughts!
Graphics:
Oh man this game is gorgeous. I can't get over how pretty the world map is. You can see the shadows of the clouds passing overhead, the beaches are a lovely vibrant blue in the shadows, there's WEATHER... And the whole game is incredibly detailed. Visit a town when it's raining, and you'll see the rain outside the windows. Nice :)
The areas aren't that original - capital city, frontier town, small forest, ancient ruins, etc and the progression in the beginning of the game is exactly the same as in Tales of the Abyss. Seriously, your first dungeon is a forest. But it's also clear that a lot of thought went into designing the world and making sure everything fits well together. There's really a sense of unity of design. They've also taken a page out of Square Enix's book by adding flashing lights everywhere, it's fun! Reaching the town of Nordopolica for the first time and seeing the fireworks against the Northern Lights is really a spectacle :)
Namco has also improved their cutscene direction considerably. There are still plenty of scenes of people standing around talking, but there are also awesome action set pieces that are much better than, say, Jade's fight with Largo in Tales of the Abyss. Even entering a town for the first time is occasionally livened up by low-angle shots out of Kingdom Hearts. Nice job, Namco!
Sound:
Well they've reused the same sound effects as in Tales of the Abyss 8D They do use some neat ambient tricks, like adding a vocal track in a bar to emulate the hum of conversation. I wish it were a little longer though, because the short loop makes it a little annoying.
The soundtrack is interesting, because a few tracks are clearly trying to do something different, and the other tracks sound exactly like every Tales BGM ever. The music in the town of Dahngrest is amazingly ambient and really helps bring the town to life, while the music when you're sailing around could be easily retrofitted into one of Sakuraba's old scores without anyone noticing a difference.
Gameplay:
This game is really the complete package. A full-length story, an awesome battle system that's even faster than Tales of the Abyss's, plenty of subquests, eight playable characters who all have full movelists and developed interactions with the other characters, an item-synthesis system, small treasures littering the world map to give you incentive to explore... My only complaint is that some of the towns are too small with blocked-off areas (Heliode is the most frustrating). I guess it's a downside of the lovely HD graphics, so I bet FF13 must be even more frustrating that way.
Characters:
I think if I had to summarize the characters of this game in one word it would be 'pleasant'. This sounds like I'm damning it with faint praise, but I'm really not. The conversations don't have the acidity that often marred the skits in Abyss, and the main character is more mature and self-confident, so he's not as crushed by setbacks.
Honestly this game demonstrates what an influence the main character has on the atmosphere of a story. Yuri is confident, accepting and laid-back, and he can take the other characters on their own terms without being too weirded out. He's also cynical without being gloomy, so we don't have any excessively naive speeches or any melodrama either. He's maybe the most mature Tales hero I've seen since, hmm, Cless? He actually reminds me of a main character from the Summon Night games, since he's so calm. However, since he doesn't really want for anything he's harder to love than Luke was. Luke had such a horrible time I wanted to bake him cupcakes and draw pictures of him and give him a big hug and on and on. For Yuri, I just want to stand in the background and clap as he throws rocks at obnoxious people 8D
Estelle is like Luke from Abyss - a sheltered member of the royal family who discovers the real world for the first time - and she even has a swordfighting teacher she really admires. XDD But she's clearly had a more normal upbringing and is also more bookish, since she's apparently memorized every book in the imperial library. She actually reminds me a LOT of Nagisa from Clannad (not just because they're both voiced by Nakahara Mai).
Flynn is interesting, because his characterization is a little different than I expected. He's not hopelessly naive, and Miyano gives him a low voice that makes you realize he grew up in a slum like Yuri and has a strong will. He and Yuri actually bicker much more than I'd expected - instead of being close friends who hang out a lot, you get the sense that they trust each other a lot, enough to let each other go their own way. They remind me of Ed and Roy from Fullmetal Alchemist a bit in that Yuri trusts Flynn to reform the knighthood, in the same way that Ed trusts Roy to turn Amestris from a war machine into a real country.
And Flynn trusts Yuri with Estelle! Given that Flynn is the 'holy knight' type, it's actually kind of awesome that his knighthood doesn't interfere with his brains (or at least it hasn't yet)
For the other characters... I LOVE that one of your party members is a dog. Who participates in skits. By barking. Rita is a high-quality tsundere (I can see why
skuldnoshinpu is such a big fan of Estelle/Rita now), Karol is a very realistic little kid, Raven is properly annoying, and Judith is cool.
And Patty is hilarious. Yes, I know she's a loli pirate who got added to the PS3 port, but she fits the game so seamlessly that I'm having trouble imagining Ragou's mansion without Patty hanging from the ceiling, or your first ship ride without Patty's commentary...
Also it's just a nice feeling to play a game where the main characters want to make their world a better place to live in.
In short: A more than worthy successor to one of my favourite RPGs ever. Namco, release the PS3 version in English so my sister can play it, willya?