I don't think it's worth it. We did a 3 day
DCL cruise on points in 2001 but, wouldn't do it again for several reasons including: too many points, fees to book and more fees to change a reservation, restrictions on the points if you have to cancel and we don't like to wait for the 11 month window to book our cabin.
We've done three additional DCL cruises, 1 three-day, 1 Eastern and 1 Western on cash and we've found very good fares by booking whenever the new rates get published. For example the April 2007 rates are on the DCL website now.
We currently have 2 DCL seven-day Western cruises booked with cash. One in October 2006 (Cat 5 balcony, 2 adults, $3,150.22 includes tax and insurance, then we get a bonus $200 onboard credit) and then another in December 2006 (Cat 5 balcony, 2 adults, $2,916.22 includes tax and insurance, then we get a bonus $200 onboard credit). For us cash is a much better value, especially with the rates we've been able to get. Booking as early as possible further allows us to book the exact cabin we've come to prefer.
I've found renting points to be easy and enjoy meeting the renters I work with. So for us renting out our points and paying cash suits us best.
Good luck with whatever decision you make and please travel safe.