Pros
Money is good, and Paypal deals in money. Huge customer base, so be assured that company will be profitable for long time. Who doesn't love free snacks and free ride in AC buses. Flexible working hours with an option to work from home sometimes. Not much work to do.
Cons
Even though its a product company, work culture is same as service companies. People just want to finish bare minimum or if possible twist the project requirement and push testing guys to just pass the code as the way it is. No proper knowledge transfer programs for new hires and no proper documentation for new hires. While there are some good articles, they are scattered on so many different websites that while searching for something you will feel like you are on a treasure hunt, and believe me you will feel same kind of joy when you find something worthy!! While the whole world have moved to modern technologies which are easier to handle and more intuitive to work with it still uses cgi implementation using C++. In my opinion not more than 1% of people in Paypal Chennai know how the whole system works, right from the frontend to the backend, I don't know about the other offices. There is so much mixup of different technologies, so much of real work done on patches and by porting software, that you might get a feel that if ever someone sends Paypal code as an entry to some collage making competition, no other team will have a slightest chance of winning. You have to work with a crowd of people where you won't find inspired by anyone. This is especially a bad scenario for you if you are in early stage of your career and you want to have a mentor. Moving from one team to another is very difficult, unless of course if you have something to blackmail, like another job offer. At last the most important thing, it will entrap you with all the joys I mentioned in Pros, make you a worthless person who doesn't know anything about the latest technologies, who does not fulfill any of the criteria of a good software engineer. So you are bound to live with Paypal and die with it, unless of course if it throws you out.