[Note: I haven't played SO3 -- my brother did. I just never got around to it since it came out during finals while I was at LCC...]
Quick: It's very Star Ocean, and yet it's obviously made by Squeenix and not just Enix+Tri-Ace by themselves (in design and composition this is obvious). Star Ocean being Star Ocean, this means that they built this game for the crazy, obsessive ones.
So far: 8.0 out of 10.
Strangely enough, the translation went way up while the voice acting went down. I'll try the English voices again later, but for now I'm keeping it in Japanese. The translation, however, makes it annoying in that the attack names are not the same. I don't know why they couldn't use the usual Raise Dead (Restoration), Growth (Enhance), Protection (Enshelter), etc.
Story: Takes place before all three games before it, merging the regular calendar date with theirs. About 330 years before the first game, to give an estimate. (*cough* the beginning of SO1, I mean.) You run into races and planets that all three games visit, although the circumstances are very strange. It follows like a proper SO game, although there are apparently less variations than other games. (I was expecting to have a major event splitting character choices, for example. Somewhere in my head I still think it will happen.)
The more you know of the series, naturally, the more rewarding the storyline is. Leaves much unanswered, like all Star Ocean games. (I would be disappointed if it didn't.)
Gameplay: A smoothed-out merge between the first (SO1&2) system and the second (SO3). So no MP death, but much more complicated and involved than even the PSP versions. Galaxy is available right-away, but I haven't found any information yet if the same differences between Earth and Galaxy exist in addition to the stats. (That is, I need to find out of exp and AI differences exist.) The battle magic system is a combination between SO3 and the PSP versions.
Item Creation: Not as exciting, but much more reliable. Still, item creation is still a must since it's a trophy. Field commands also supplement this (what would be called variations of Survival in the first two games). Also not quite as varied as what it used to be. Music and book-publishing, for example, don't seem to exist in this game. Not to mention calling birds. The sell-price booster is still there, but is almost worthless when you don't sell anything anyway, and the selling price even after maxing it is still too little to be worth anything.
Battle Trophies: As with the third game, there is a separate system in addition to the trophies (achievements in the 360). In the second game for the PS1, it was voice credits. Things to do while you're grinding for quests and levels... and maybe just getting out of the place. You'd think that they'd learn from SO3 and make some a little less ridiculous, such as jumping 5,000 times. Who wants to make the worst jumper jump that often?
Mapping: None of the PS2 bs that you had to go through. It's not random encounter either, so the maps are big. You can dash all you want, but it's still going to take you a while to get somewhere. (I wish the bunnies were faster.) The camera annoys the hell out of me, though.
Music: Not particularly there. A few ones hark back to the other games, but SO has never really been known for great music... So at the very least, it tends not to be too annoying.
Relationships: Well, I haven't seen the ending yet, so I don't know how it's going to go. For all that the SO community (in whatever language) goes on and on about any pairing under the sun, by tradition it's almost purely hetero. (I say almost because everyone remembers the few PAs that push this line.) As a result, I doubt it. Also like all SO games, a few of the main pairings are always featured in the storyline itself, even though you can totally trump that.
Characters: As I said before, I was expecting more of a selection. The character types are the usual type, although strangely enough, there are more mages than anything else. Two combat mages, one support mage, one support fighter, three fighter-mages, and two melee fighters. Tons of healers... which is probably why the AI doesn't seem to stress healing you when you're hurt... (SO1 was the most interesting in that you had no healers for a long time...)
Trophies: I'm pleased to note that they're ones that no one (except a few) will platinum. I'm annoyed that quite a few seem to be related to the ending, but I can't tell for sure. It's kind of :/ that a lot of the trophies are bronze (frankly, all the storyline ones should be bronze except the best and hardest ending to get and make more of the completion types silver and the 100%'s gold)...
Squeenix: As first impressions go, it doesn't give much of a good one for SO fans. Especially SO fans that don't like Final Fantasy. Later, though, it sheds the Squeenix feel and goes more into the SO-ness of it. Like all SO games, the sci-fi aspect of it is minimal (that is, nothing original or innovative). Surprisingly enough, though, they bandy the term "star ocean" more often than the series ever did before...
Future: Given this one, I can see more games on the horizon. Still, it feels like they're pretending that the third game didn't happen... when it should, given the tradition of having doujinshi and such inside the game.
Overall: Thankfully, not a short as the first game. Roughly equal to the second in that you can take forever to do anything, although running through the storyline shouldn't take that long at all.