We work on a six week schedule, changed to that several years ago. It always seems like it's a long way off, and some people complain that they don't know what days off they need, but we have about three weeks to work on the schedule, and it is usually ok by the time the lead nurse has to work it in to the other units. We all work 12 hour shifts, RN's only in my area.
The schedule has to be worked on only 8 or 9 times a year, not every month. Also, the six weeks usually covers Thanksgiving to about New Years, so it's easier to look at the big picture. As we have to work two holiday shifts, it's easier to see what everyone else is doing. A record is kept of holidays worked, to make it fair for everyone.
We are allowed 6 "R's" on the schedule, we can even use those to extend our vacation weeks out at either end, as long as it fits with everyone elses shifts. Also, full time staff must work 5-6 weekend shifts, PT 3-4. We don't rotate at all.
I used to work regular days every two weeks, but I like this better. Some people like to work their shifts in a row, and others no more than 2 at a time, so we try to accommodate, but we can't always keep everyone happy!