Pros
I've enjoyed a lot of very good years with CGI. There is a lot to like about the company. But it all depends on where you are - it can be like working at a very different company when you move between groups.
Cons
Company is definitely in a bit of a rough patch. The core model is when where you can feel like the company is shrinking even when it's growing. Big on acquisitions, so they buy to grow but then cut redundancy so there are always people being let go. Now with the recent press, etc., if you are in a part of the company that is getting hit with slower growth or even negative growth its not a very happy place. Very high turnover, and it's the good people who are leaving. That's been going on for about 2 years now. Folks think the worst is behind, but I'm not convinced.