While it is a good game on its own merits, it doesn't live up to Saints Row 1 or 2.
The campaign takes place a few years after the events of Saints Row 2, with the Saints becoming celebrities. They have corporate sponsors and energy drinks in their name and have Stilwater in the palm of their hand. However, when a bank heist goes wrong and they get thrown in jail, they get bailed out by a criminal organization called the Syndicate, made up of three gangs, the Morning Star, the Luchadores, and the Deckers. In exchange for most of the Saints' profits, the Syndicate will let them go. Of course, the Saints refuse, and they begin a war with the Syndicate in their city, Steelport. The Campaign is quite lacking in SRTT, as it is way too short, and incredibly easy. Your phone gives you the option to purchase abilities with cash, such as increased health, increased bullet damage, less damage taken from enemies, etc. So basically, it is as if the game is giving you cheat codes as you progress through the story, which makes the already easy game basically play itself.
Also, the gangs and city are incredibly lifeless. In SR1 and 2, Each gang had a unique identity, and as the story went on, we learned more about them, got to know them more. That is not the case in SRTT, as there is almost nothing known about each gang, other than the fact that one gang is a group of hacker nerds, one is a group of luchadores, and one is a group of sophisticated mobsters. Steelport is also an incredibly dull city compared to Stilwater. In Stilwater, there was so much more ambient activity going on in Stilwater, and citizens were plentiful, while Steelport almost feels like a ghost town, and the citizens are boring and provide nothing entertaining to the game.
Besides the campaign, there isn't a whole lot to do in Saints Row: The Third. If you have a friend who has the game, you can play co-op over Xbox Live, but the campaign is the same and there aren't any differences between solo and co-op besides having a friend with you. There is a new mode called Whored Mode, which is similar to Call of Duty's Zombies or Halo's Firefight, in which you have to fight off waves of humorous enemies, like guys dressed up as soda cans or giant hookers. While has its fun moments, it won't keep your interest for very long.
As a fan of the Saints Row series since the beginning, Saints Row: The Third was a huge disappointment. Saints Row 1 and 2 had the perfect balance of seriousness and silliness, while SRTT has thrown that out the window. Now, instead of getting an engaging story with plenty of funny moments, we have a lackluster story filled with fart jokes. It feels like Volition has completely abandoned the fans of Saints Row that got the franchise to where it is today, since Saints Row gained its popularity as a game about gangs and gang warfare, not fart in a jar or giant **** bats.