Pros
I've worked for 5 companies, large and small, since I started my career 17 years ago. This is, by far, the best. The pay is solid, the company plans fun events for employees, the hotel discount is fantastic, the company's branding and communications make me proud to work here. Most coworkers are nice, fair, and even fun. But it is a large company so there are exceptions for sure. Senior leaders make sound business decisions, which have made the company the leader in its industry. If you don't like your current role, it's fairly easy to find another position internally. The Marriott family and the CEO feel strongly that it's important to strike a work/life balance and they encourage us to spend time with our families and get enough sleep. :)
Cons
There are 2 things that bother me - the annual survey doesn't do an adequate job of identifying and fixing problems in the workplace. Marriott doesn't really use it that way (HR, you know what I mean). So employees just need to leave the company or switch internally if they don't like their situation. In particular, Marriott needs to do a better job of weeding out the terrible managers who demoralize employees. I also don't like the way the 401K is set up. An employee needs to be at the company for a long time before the 401K match kicks in, THEN the match for your full year doesn't get deposited until many months after the year is over. I was there for 18 months before getting any match.