I've played for like 42 hours now, some of my thoughts (spoiler free)
- mog clock/random enemies: I really don't like the new encounter system, I'm the kind of player that likes to stop and look around a lot, read text on the walls, watch the scenery etc, overall I play with a slow pace. The enemies popping on the map kind of ruined that feel for me here, I still could do that mostly but in some areas it gets really annoying.
The other thing for me personally, I like watching monsters roaming around in the map, I get the impression of 'wild life' in world from that, the world feels more alive to me like that, I personally thought Archlyte Steppe in FF13 was really cool first time I saw it, so was FF12. Now walking through empty spaces and enemies appearing doesn't feel good to me at all, there are still very few visible enemies, mostly the more bigger ones, but it doesn't feel as good as before at all, ymmv.
- graphics: some areas look very good, most are ok, some are just ugly, there are some very bad textures in this game. Framerate if you watched that analysis, it's the cut-scenes that can get bad sometimes, normal gameplay runs well mostly.
- battle system: as was said by others, yeah I think the game is easier than XIII too and I thought XIII was easy, so much that I don't even need to bother much with changing or customizing paradigm mostly. What I really liked in XIII was that buffs and debuffs were really important, I think they were handled the best there in the series, managing them and exploiting enemies weaknesses I thought it was very fun, here though they don't matter much for the most of the game so far that I played, I hope there are some more optional enemies that take more than usual to defeat, most battles here end very quickly for those things to matter. Omega battle was ok but nothing hard, I wish the colosseum was in the game already with a dozen of really hard enemies. I hope they consider a hard mode in future, just add something to stats of all enemies or something. again ymmv, depends on the player I think. overall FF games are not hard games but still I like more challenge.
There is the monsters inheritance system that lets you give new abilities from one monster to another by sacrificing one, I haven't really experimented with it yet because there was no need to, I wish the game encouraged these more with better battles for example, there are few cool monsters to get, customizing them is pretty good but still I'd rather have just another character.
- very few characters: I personally like plots involving quite a few faces, I like to meet new characters as story progresses, I thought XIII had a good balance, not too many, not too few. XIII-2 has very few characters relevant to the story, and the story part of the game is pretty short, I did it in 21-22 hours I think. I'm not going to say the story is bad or good, you have to see it for yourself and form your opinion on something like this, I think it was kind of entertaining for me personally but I prefer XIII's story and themes overall if I had to pick.
- Level design: some of the areas are pretty big, there are lots of branches to get around. some areas are comparable to hub cities in Mass Effect games if you played those. level design is better, you can go in whatever direction in some areas, some areas are more linear. I think it's a pretty good improvement over XIII.
- Costumes: they said they made the cut-scenes realtime so that you can see the changes in it but it doesn't look like there is any costume in the game right now (anyone?), looks like all of it is DLC, I don't think I will return to this game in a couple of months just because of a new costume, kind of waste, they should have had a couple in the game at least, there are just two characters, it's not much work.
- Music: I wasn't a fan of vocals at first but in the game they don't sound bad, I like that they experiment new things but I hope next time they don't do this. theme songs are good. Lots of returning music from XIII used very well in the game, overall I think it's better than XIII.
- Live triggers and cinematic action (dialog choices and battle QTE) they are pretty cool, they add nothing meaningful to the game though but still good to have I guess. QTEs are too easy and some of them in battle cut-scenes give a choice and change the scene a bit.
- Mini games: Xanadu only has chocobo racing and slots right now, then there are time labyrinth mini games. I never cared about mini games in RPGs, they are ok I guess, nothing special.
overall I think XIII does battles and encounters better and that was what I really cared about in the game, here it's a bit disappointing. I still prefer XIII between the two.
I don't care about review scores but right now I'm wondering what scores this is going to get from western critics, if I had to predict, I'm thinking 7.0-8.5 range.