It can work the other way too, Hank R.; there is always the possibility of a last minute bargain. If you are flexible enough to go on short notice, and you are not particular about the catagory or location of your cabin, then yes, it could be worth waiting. It is said often here that there is no such thing as a bad cabin: some are just better than others. And some folks just get a kick out of finding a good deal.
My approach is this: when I see a cabin I like on a ship I like at a price I think is reasonable, I go for it; no surprises--no disappointments. I usually book a year or more ahead and I have yet to see a price go down from what I paid.
I agree! I had to tell my T.A. about the drop in price on my next cruise. They don't always have the time to be checking prices. However, I have been called by my agent in the past with a price reduction—she just happened to see it before I did.
As noted above, it is good to check on it yourself. My agent is great and she typically finds out about a price drop before I do, but not always. Good agents have lots of clients and can't stay on top of every booking all the time.