Pros
Good for people who have had trouble obtaining a job. They dont require you to sign a contract when they accept you, so you can basically continue to look for other opportunities until 2 weeks into your start date - as thats when you are locked in. They provide you with paid training for a certain number of months depending on which stream you take. What I found particularly useful was the SQL and UNIX training sessions as they are structured very well and the complimenting materials and exercises very quite helpful. In my opinion, the training session serves as buffer time where you get to improve your own skills while the account managers are searching for openings for you to get places. The goal is to basically get you placed at a client site asap. Its better for them, because then you are no longer a liability for them, and its better for you because then you're getting paid more. If you get lucky you can even skip out on some of the training due to being placed early; which is definitely a plus because you will start getting paid more sooner.
Cons
Pay is not an amazing amount but you will be able to live comfortably. Not extravagantly though. They give you a fixed rate where as the client you are placed at may be paying them a lot higher. Contract is for 2 years, which I guess is fair given that you are guaranteed to land a job at a client site.