Pros
Most people including me would chose flexible work hours for the best reason to work for Oracle. Normally, you will just need to complete your project in a timely manner, and you manager would not count your work hours. Sometimes, I have to work late or weekends to finish up my projects, but I am also very comfortable to get out of work early for my personal matters. Of course, it is the best place to learn Oracle application products and databases. They offer excellent training resources such as Oracle university.
Cons
The company is huge , and I often found poor internal communication. Definitely, compared to a small software company, it is very hard to move to a management position from a developer. There are many developers who have been there more than 10 years and still have been waiting / looking for an opportunity to get promoted to a management position.