There are no other ships with engine problems at this time, only the Star. The Dream has been fixed. As for these types of problems, beleive it or not they are not unusual. Celebrity's top ships, the M class have all had similar set backs.
Don't feel to bad about missing Acapulco, read some of the other boards. You will learn you aren't missing much. Spending 24 hours there would not be the most exciting thing you could do. Just enjoy the entire cruise experience, the ship is very nice and crew outstanding. What a great way to start the New Year. NMnita