I have seen on the boards here where people will say how many rooms are left in a particular category or what percentage of a category is filled. Where do you look to get this information? I was just curious what percent of rooms on the cruise I am on are full.

There is no accurate way to get this info. What you can tell is whether there are 7 or 8 unassigned cabins in a given category. If you are really into it, you can go to the DCL site and attempt to book each cabin on the ship--those you aren't able to choose are assigned to someone else. The problem with this approach is that you have no way of knowing how many unassigned gty bookings DCL is holding. Sometimes when talking to DCL, a CM will say something like "the ship is 90% booked." This gives you a rough idea, If they have released restricted bookings, CM rates, TA rates, or whatever, you can assume that your ship is not full.

It's a little more complicated than that.... Aside from the ship having a finite number of cabins, each lifeboat (which has a group of cabins assigned to it) has a maximum capacity... Also each of the kids age categories has a maximum capacity (based on the number of available counselors). So, it is very possible that there are empty cabins on the ship (or in a certain category), yet no further reservations are possible. When the ship starts "filling up," you'll start to notice that reservations are possible for a cabin with 2 people in it, but the same cabin cannot be reserved for 3 people... Or you won't be able to do a reservation for a family of 4 with 2 kids, but a family of 4 adults will work. You can get a decent idea of how full the ship is by trying to get a reservation with 1-2 adults in a cabin... See how many categories/cabins are available as you go through the reservation process.