Man was I glad when my Crisis Core package arrived. I've been already playing this game since Wednesday and have played 7:30 hours until now.
Crisis Core, in contrast to Final Fantasy VII, does not have tactical battles. In fact, they're the direct opposite: They're random. Really random. Well, of course entering a battle was always random for Final Fantasy VII, but in Crisis Core even your special attacks, materia upgrade and Level-Ups are random! Who on earth had that stupid idea? There's a slot-machine-like thing called DMW (Digital Mind Wave - wtf?) in the upper left corner which spins while you beat your enemies. It spins pictures of characters and numbers. When the pictures match on the first and last slot, the "Limit Verge" appears and depending on the outcome of the middle slot you'll execute a Limit Attack.
Everything here is absolutely not influenced by you in any way. You can't tell the slots when to stop, you can't do nothing. Depending on the outcome of the numbers of the Limit Verge you or your materia might level up if the numbers come out right. Theoretically this means that you can gain two levels in twenty seconds or gain no level at all in 5 hours. More fighting doesn't necessarily increase your level either. Well, obvisouly Squeenix was smart enough not to make it as random as a true random number generator, but it's still unpredictable.
The Limit Attacks are somewhat strange, too. Sometimes there are some FMV sequences that tell a part of the story -- right while you're battling totally unrelated enemies or you are on a mission or something, before the attack begins. I don't understand this at all, it makes no sense to me.
You don't have weapons with materia slots, either. In fact, you don't even have different weapons! Instead you have a fixed number of materia slots where you can put your materia, which sometimes increases when finding special items or so. At least you have two Accessorie-slots in the beginning... but again, no weapons. This actually pisses me off most. There are no connections between materia-slot, no slots with doubled materia-exp-increase, no new weapons that do more damage, nothing.
And then there's Material Fusion. You can fuse any two materia together to gain a new one. The outcome, however, is always sooo teeny-weeny better than the originals that it almost never brings you a significant advantage. Plus, you can't predict the outcome at all and sometimes you basically just lose one of the materia, while the other stays the same. Absolutely useless.
Then there's the difficulty of the game. Being a hardcore-gamer I picked the Hard Mode over the Normal Mode. It lasted 30 minutes and I nearly threw my PSP through the room, out of desperation. I died multiple times on the first hard enemy, and the bad thing about that was that there's 5 minute sequence that YOU CAN'T SKIP before that battle. Oh jesus how I hate this! That was the reason why I didn't finish God of War, too, by the way. Un-skippable sequences are the most sinful thing a game-developer can ever do. (By the way: In Crisis Core you can ALWAYS interrupt the game by pressing Start. This somewhat makes up for not being able to skip sequences... but only somewhat.
So I decided to start from the beginning in the Normal Mode. This was a good decision, because the game basically becomes child's play after that. It's actually so easy that it's making it boring at times. Most of the time, when hitting the enemy, it's pushed back and gives you time for the next slash. This makes matches where you don't get a scratch on more than common.
The mission system is used for leveling and resembles Monster Hunter in many ways. Because you're more often in areas without enemies than you were in Final Fantasy VII, it's harder to run around and level up as I often did in the original. The missions kick in here, which you can enter on every savepoint. Pick a mission by category and difficulty, enter it, beat it, get a reward, go on to the next mission. Those are always in the same environments, like the various levels in Monster Hunter. Missions are actually a bit less boring than running around on the field to fight the same monsters over and over again. That's what I did in Final Fantasy VII for hours... or well, actually even for days and weeks. :-)
Oh and here's the moooooost disappointing thing ever: You don't have a party! You're always running around alone as Zack and you can't switch party members! That's so unbelievably boring!
There are good things about the game anyways and it's quiet fun to play, but I must say that I would have more fun if I put FFVII on my PSP again and played that for the nth time. It's just so much more tactical and muuuuch deeper than Crisis Core. Crisis Core seems to be meant for the occasional gamer and not the typical Final Fantasy RPG fan. It's more an action game with a good story than an RPG if you ask me. I hope that there are at least 60 hours play-time in that game, but I'm not too sure about that yet... I'm looking forward to find out more as the story continues, maybe I'll write some positive aspects of the game after I've finished it.
That being said, the game is still much fun. But again, it's not as much fun as Final Fantasy VII was.