Interviewed with PayPal after graduating from college in December 2013. The process took about a month.

It consisted of two phone interviews, followed by a final on-site interview which comprised five hour-long, face-to-face rounds.

There were no difficult algorithmic questions. If you know your basics on algorithms and data structures, you should be fine (I was asked a tree question and an array pattern search question).

I interviewed for a position in mobile SDK development, so the interviews focused mainly on architecture and design. Practice your object-oriented design and think about how to design things securely and to scale (client/server side caching, security, etc.). These questions can be particularly tricky for someone coming right out of college.

Also, PayPal values a good culture fit, so be enthusiastic, sociable, and confident.