Everything you liked about the first game is here.
There are only 3 big cases in the sequel, but the game starts with a short tutorial case which I found boring to play through because I already new how the game mechanics worked from playing the first game on DS.
The soundtrack is largely the same, the only real difference is you will be hearing remixes of familiar themes from the first game.
The psyche-lock feature is interesting, yet flawed. Basically you present evidence to people to open up new lines of questioning. You get some form of “health” bar, but outside court this is flawed as if you lose all your “health” you get to go through the process again. If you die in court, well it's game over.
Like the first game what Phoenix Wright lacks in interactivity it makes up for with really compelling writing and characters, and I found it hard to put my DS down after starting a case. This is a really long game, and took me 3 days to get through. I found that the chapter stops to be a bit too long, but you do get to save your game whenever you want.
I personally recommend this game to fans of the first, but keep in mind that this game isn't as effective as it was the first time round, theres a large sense of been there done that about it all.
Anybody new to the series would be better off buying the original and playing that first, it is the better of the two games.