A constant feeling of being overworked and rushed. 45 hour minimum workweek. When there are deadlines and there is much more than 45 hours spent at work, you are rewarded with a certificate, and if your lucky, some time off shortly after (20% of overtime worked). The work environment changes greatly with the area. Some are much more overworked. There are definitely teams and areas that are to be avoided.
A major con for me was that the job was an IT job more than a CS job. The programming was fun, but I felt like I was solving the same types of problems every day. There was no thought to computational theory or efficiency, just to ship a product by a specific date, often leading to half-baked, 70% done projects considered complete, which leads to a cycle of replacing legacy systems every 5 years.
There are big pushes to innovate, yet no measures are given to provide for an innovative atmosphere. Everyone has the feeling of being overworked, and is told that to spend any time to innovate, it must be done in addition to regular work hours. Freedom is not given to explore new technologies (there is a team for that, and must be approved by another team to get access, a lengthy process). Work areas are crowded and noisy. Not a place to look for luxuries, Walmart in its culture looks to cut costs, meaning minimal solutions/work place (It took months of pleading, begging, complaining; eventually by entire department to get a second monitor).