I had a cruise cancelled due to cruise line rerouting. Due to the lateness of the cancellation, I was able to convince the cruiseline to give me what was in fact a two category upgrade since the lower categories were already sold out on the ship I swithched to. This cancellation was 10 months before sailing. If you were damaged, ask for compensation. If not, don't. Rebook on Star. If you are forced into paying for a higher category, ask for free upgrade. I recommend that you not delay as there were a lot of people in the same situation as yourself.
My only comment on compensation is that it seems to be a hot topic on cruise boards--what people got for free. I think it is unfortunate. I read of one guy on Carnival that spent his whole week videotaping perceived problems so that he could get some compensation! If his cruise was ruined, it was due to his own actions.