Argh, I was going to start one soon because I had a fairly epic "Dragon Quest VIII is a super-grindy piece of garbage" rant in the past, but I like this one much better.
The first thing I noticed about the game is it has the best translation work I have ever seen. Seriously. Puns have been either translated in such a way that they work or simply inserted. Literary devices dominate discussions with everyone, and overall it's a joy to read the text. +5 good points.
The music is pretty standard DQ; I find it kind of forgettable for the most part but since we're talking about a handheld system I'll withhold some harshness. +1 good point.
The artwork is where the game kind of falters. It's not Squeenix's fault; the DS just isn't powerful enough for a decent 3D game and they've done a marvelous job considering its weaknesses. The landscapes look good, and key NPC characters look really great. The monster art is great. But the whole "create a hero" aspect seems like it's taken the personality of the PCs.
RE: the difficulty, I'm not sure how it gets counted as the hardest in the series, but to that end I beat the game on Sunday and I'm only now approaching the 50s. So far my toughest grotto had Shogum at the end and he was a little more boss than I expected. Unfortunately it looks like I've got a lot of grinding to do before I get the tougher grottoes; not sure if my interest will last until then. I can definitely say the difficulty is inconsistent. Some bosses were pushovers when I was underleveled; others seemed to get lucky and would land criticals on my mages every. single. turn.
I'd call this game much less difficult than DQ 8, if only because the story quest didn't require anything that felt like extra grinding. DQ 8 required a ton of it, and I really don't enjoy being forced to grind.
I can say that what I like about Dragon Quest vs. Final Fantasy is that buffs really matter. In FF the only buff spell I consistently used was Haste. Usually a black mage could do more good with a damage spell than a buff and a white mage could do more with healing. In DQ, you are pretty much expected to buff the heck out of yourself and debuff the boss. Oomph feels like it adds about 30 levels worth of power to my physical fighters. A double Buff makes me shrug off damage like I was 15-20 levels stronger. Hitting a boss twice with Sap adds 5-10 levels worth of damage, and if a double-Blunted boss hits a double-buffed character the damage is laughable. It's a bit annoying that most bosses can Disruptive Wave your buffs away, but sometimes that's a plus since you might rather have the boss steal your buffs with their turn than pull out a high-damage multi-hit attack.
The class system is interesting but I have a bad feeling it's broken. Near the end of the game, I had a level 40 Paladin with Forbearance, an ability that directs all combat damage to the Paladin. Paladins have *sick* defense and high HP already, and in many fights it was well worth sacrificing a little damage output to ensure a wounded Priest didn't get KO'd by a random attack.
One thing that bugs me is how Tag mode/multiplayer is so fun but just isn't a good match for the US. The only time I've had a chance to do multiplayer was at the GameStop event last Saturday. It was *really* fun, but no one was interested in setting up a regular playtime so now I don't have anyone to play with. It's a crying shame that it can't be played over WiFi.
All in all I'd say this game's a gem unless you really don't like the DQ style of combat.