There are lots of good things about Bulletstorm, a modern, gory, vulgar FPS with a beautiful color palette, interesting level design, and a focus on very specific gameplay to boot. I'm sure you're aware of the SkillShot system. Multiple weapons with unlockable secondary fire that awards skill points for successful, and specific, shots and combinations. Grab the pistol, blast a flare into a group of enemies, then thump them into the air as they're on fire, and take them out one by one and watch as the points pile up. Bulletstorm also makes use of a tool called a "Leash" that allows you to yank enemies towards you and then boot them into environmental hazards like spikes, malfunctioning computers, and man eating plants. You can also perform the aforementioned Thump which will send enemies flying into the air to setup a chain of SkillShots. Gameplay wise, Bulletstorm is a clear winner.
The setting is very lush. Beautiful use of color in a some what tropical environment. It somewhat reminds me of a few locations in Borderlands, another title with a good choice in color arrangement. Post apocalyptic - Society has Failed and now Here Come the Freaks - gore fest. The only problem is that the final third or so of the game trade in the beautiful locals and crazed characters for your typical FPS trappings. No more shopping malls and blue butterflies and radiated neon green berserkers. The End Game is mainly your tried and died pile of bodies, spooky monsters, a sewer, decayed buildings, and eventually a derelict space shuttle. Yawn. I will not spoil the ending outside of telling you that there practically isn't one. The most epic of boss fights happens about half way through. The final missions of the game are you racing against a clock while firing on your generic "Space Marine". Since you're on a timer a few times during these final sequences the SkillShot falls to the wayside and you're playing a medicore FPS. There is no end battle. Little closure. You merely reach a goal post and the credits roll, but not before getting setup for a sequel.
While this is more or less a let down and not too terribly out of the ordinary, the major problem with Bulletstorm is the story. Almost everything else about the title is a move away from the traditional FPS mold. The story, on the other hand, is tried and true super cheese with a few ends a little more stale than others. While most of the title has you focusing on SkillShots titled "Gang Bang", "Ejectulation", "Rear Entry", etc, the story completely lacks any of the otherwise established sense of humor. Gray, your main character, fits right in. For half of the story. By the time you get past the big reveal Gray turns from a foul mouthed frat boy devolution into a sincere, serious, man who seeks redemption. The characer growth is hasty and poorly executed in light of the humorous intent behind the rest of the game.
Echoes mode is a fun diversion. Did you play Bizarre's The Club a few years back? Well, no, probably not. But it was a really good game and Echoes is a continuation of The Club's formula. You go through scripted sections from the main campaign in a score attack mode, competing to have your name at the top of the list.
Anarchy is Bulletstorm's version of Firefight/Horde/Onslaught from FPS juggernauts before it. It's nothing out of the ordinary. You have a score limit set that requires you and a team mate to dispatch certain enemies certain ways to get crucially needed bonus points.
There really should have been a multiplayer deathmatch. Yes, it would be out of place, and no there probably wouldn't be a way to implement the Leash in a balanced and fair way, but the environments and the weapons are unique enough that some form of deathmatch would have been a nice addition.
I beat the campaign in around seven or eight hours. Don't expect to go back through it on Very Hard, may beat the last few Echoes levels I haven't completed, and the only thing really tempting me to go back to Anarchy is an achievement or two. If you're interested in Bulletstorm from the beginning then you should be comfortable with making a purchase. If you're on the fence I don't think there's enough in Bulletstorm to make it worth it.