Well, like I'd mentioned, I had lots of fun with the game when I'd learned how to exploit it easily, and the battle system/movement is faster paced. Normal battles are a lot of fun to experience, especially on Hard (you don't unlock the hardest difficulty until NG+).
Don't let me deter your hype by any means. The running joke in this thread happens to be that I hate video games because I make long posts about games I've just finished... especially for the ones I don't enjoy. (BTW, it isn't true; I like video games! I've just played a lot of them to be more critical. >.>) But I enjoyed my time with Xillia's battle system, and the better cinematic flow of delivering dialogue. Towns are very nice to look at, being able to switch characters on the fly mid-battle is highly desirable (ie: you can switch characters in the active battle party with characters in standby as you're battling with R3), and fast-travel with R3 saves a hell of a lot of time. There is no airship, so R3's fast-travel is the alternative.
With respect to the environments, there are some cubby holes that you can crawl into and elevated areas that you can climb up for treasures or sparklies on the field in order to use to level up your shopes, but outside of that and fighting enemies, there's little design relevance for them (other than the developers showing that they have control of more scale in terms of environments, but they just don't do anything with them). In FFXII, you can do more things like fish, do quests, watch enemies beat on each other, etc. Not to mention that there are environmental conditions (ex: weather, terrain effects (ex: Dalmasca Estersand is on sand, so Earth attacks are 20% stronger than normal, etc)). So, I suppose the difference is that FFXII does something interesting with its expansive environments, while Xillia kind of... doesn't outside of leaving duffel bags and sparklies for players to grind for the treasure trophies/increase shop levels with.
So keep hyped. I think a lot of people are going to like Xillia in the west because it's more story-focused than Graces was. Xillia's just not the sort of Tales game I like because I just prefer the Team Destiny-ish games.