Pros
There is a lot to learn about the company and you go through extensive training in the beginning so you don't feel so lost when you are new. There is opportunity for advancement and the benefits are pretty good. Everyone has great personalities and everyone gets along. Also, the majority of the customers are so nice, especially the regulars. They are happy to see you and they usually tip, which the employees are always grateful for! It is not an easy job, so the tips and the other employee perks that you get makes Starbucks a great place to work.
Cons
Just like a lot of other retail/restaurant jobs, you have to stay late, often past your shift to clean up/prepare for the next day. Some supervisors I have worked with have made their employees stay up to an hour and a half past the shift. Another downside is having to deal with rude customers. But that is only occasionally and I guess you come across rude people no matter where you work. Some people like a drink a VERY VERY SPECIFIC way and they will verbally abuse you and return the drink if if you don't make it to their satisfaction (which they should be satisfied, but it's tough to have to deal with rudeness.)