First up, if you have a Street Fighter IV save data on your PS3, when you first load up the game you unlock two unique colours for each character, so that's a good bonus for anyone who owns the previous game.
The best thing about this game is that ALL the characters are unlocked from the start, so you can enjoy playing your favourite characters right off the bat, however you still have to unlock colours and taunts etc... I've noticed that I seem to unlock them playing online and in arcade mode.
As for the challenges, there are no time trials or survival modes, instead there is just 24 move challenges for each character, and as you go up you unlock titles and icons for your profile.
Online is pretty good, for me so far connecting to people has been more satisfying than the previous game.
Arcade you do get story lines for each character, don't expect too much as they seem pretty short and are just pictures being narrated by the characters, but it's still interesting.
Background music support is still available so you can select your favourite tracks to listen too while in arcade mode, doing challenges or even fighting online.
And finally there are tons of trophies to get, most being impossible to the average player like me.
Overall this game is at a fantastic price that you cannot argue with, it will bring a lot of fun and amusement to you, and is a great add on to your Street Fighter collections.