I'm writing this from the Crowne Plaza Amsterdam City Centre. The refurbishment appears largely complete. The rooms were certainly in need of an update, and the treatment IMO is well done, with wall-mounted flat-panel TVs and lots of electrical outlets.
What used to be the reception/lobby has been transformed into a modernistic (read: stark) set of podiums that unfold into a "living room" with a fireplace. Looks nice, but I'm not sure how useful it really is. As mentioned by the OP, the Club is now on the ground floor, and features more of a cafeteria seating arrangement that the previous lounge. The rooftop terrace was a spectacular feature of that lounge, and of course now all you see is pedestrian traffic on the sidestreet (the lounge is where the Amsterdammer Bar used to be). There is now a "New Dorius" restaurant in the corner, which also appears to have gone to a neo-modern styling. The gift shop appears to have disappeared, with a luggage room in its place.
The gym is still in the basement, where it is now joined by the business center (I haven't been down there yet, so I can't give a comparison with the old one that was off the lobby).
The former lounge on the sixth floor is now unused, and the staff were vague about future plans for it. I suppose it will probably be a meeting room for special events, parties, etc. to take advantage of the terrace. It's a shame they closed the old lounge, though I do suppose that now Europe is intent on making older places friendly for the handicapped, there was not much way to work around the circular staircase.
The place has an admittedly different look and feel, and frankly not all of it agrees with me. Amsterdam has a lot of old charming buildings and architecture, and the recent trend with hotels seems to be to discard as much of that as possible. While the room upgrades were more than worthwhile, the other changes just seem far too radical for me. Maybe it'll grow on me, maybe it won't. It still has the same great location, so I suspect I'll probably remain a fairly regular customer here.