After my first and second Celebrity cruises I never thought I'd see myself giving a Celebrity ship anything less than 4 to 5 stars. Unfortunately, that day has come.
My wife and I have been on many of the major cruises, but our first was on the Celebrity Galaxy in 1997. That cruise seemed to set the standard for us in cruising. We tried other cruise lines, but the two key factors that differentiate cruises for us are the service/staff and the food. Our view is that pretty much everything else besides the service and food is the same between cruise lines. Same activities, same ports, same tours, etc.
The service and attitude of the staff on Summit seemed to be right on par with what I expect from Celebrity. Very friendly! Everyone you make eye contact with while passing gives you a greeting. Another BIG PLUS I find on Celebrity compared to other cruise lines is the quick clean-up of public eating areas. As you finish with use of trays, plates, cups, etc. someone is almost immediately there to take them away. Not only does this keep areas clean, it also allows the next people to find a seat quicker. I have been on many other cruises where this is a HUGE problem.