Kazuma Kiryu is back with more allies and facing more powerful enemies (spoilers for the first game).
I have nothing to complain about the story. Although it isn't as good as the previous game, it is good enough to keep you playing through the whole thing. You'll see several characters from the previous game. Some of them are still their good old selves. Other people seem to have taken a different path in life and might surprise you a bit. Some of the new characters will be by your side from the beginning until the end. Some of them may not. Let's just say the game has enough surprises to entertain you. And, once again, if you're looking for something that gives more action than story, this may not be the game for you. The strong point of the Yakuza series seems to be the story. Which does not necessarily mean that the gameplay is not good.
If you played the previous game or even Yakuza 3 or any of the spin-offs, you'll feel familiar with the gameplay, for it didn't seem to change much. What made a great difference, specially compared to the previous game, is that the target-lock feature works far better (but it is still not working as good as in Yakuza 3). The Heat Actions work as before, the level-up system and abilities work in the same way. You can still pick up objects from the scenario to use as weapons as fire weapons are as useless as in the previous game, since they cause little to no damage to the enemies.
One thing that was in the first game but now has a stronger presence are the Active Time Events, which happen more frequently during the fights. While I don't completely disapprove ATEs, I wouldn't complain if the time reaction weren't so short.
The background sounds seem to be as good as the previous game, but without the irritating random voices loop. There seems to be a greater variety of things that your allies say if they're following you, though. If you run too fast, as soon as you stop running, Haruka will be panting. No, this will not change your life, but it is something cool I noticed.
One bad thing I noticed in the game and was probably present in the first game, but for some reason I noticed only now: as you walk through the streets of Kamurocho (or Osaka), you'll frequently see people "appearing from the nowhere". Once again, nothing that will change your life, but is not very pretty.
The minigames for Yakuza 1 are back. Bowling, baseball, the batting cage, mahjong, the casino games... everything.
The subquests are also available and now show a couple of details that may make things a little bit easier. Once again, most of them require that you fight or run from one side to the other. They may not be the most amusing thing ever, but it's a nice way to get some experience... and are a good way to spend some time in the game if you happen to grow tired of the main storyline.
With a good story and dozens of different activities, Yakuza 2 is a must-play for everyone that enjoyed the previous game.