I have yet to sail the Triumph and is one I'd like to add to my history.
Check out Cruise Critics to see if you can find some updated reviews. They seem to be a much more active board than this one; however, I say book the cruise and form your own opinion as you will always hear experiences from both sides-- good and bad. Certainly don't allow someone's bad experience to keep you from booking with a line or a particular ship. I had a really bad experience on my last NCL cruise and after reflecting on all of my past experiences with NCL, I have made the decision to not cruise NCL again, but my experiences with that line shallows in comparison to others I have sailed with. Not that they were all bad, just that they shallow in comparison-- my opinion of course. Many others seem to love NCL and prefer them over other lines. Just a matter of individual opinions.