I have stayed concierge several times. Is it worth it? That really is hard to answer!! Sometimes, it absolutely is! And sometimes, it just is not. The current prices don't make it a worthwhile expenditure over regular rooms unless you have a lot of people in one room and/or you will be spending a lot of time around the hotel. They have food and beverage offerings all day, but if you are busy in the parks you won't be taking advantage of that. The food is good but not fabulous (although my girls love love love the chocolate dipped strawberries!).
I won't discount the idea that there is a real coolness factor in staying concierge. The lounge is a great area to hang out, has activities in the evening for kids, offers a great place to relax and is very convenient when you want something to snack on or drink. We stayed there when my mom, who was elderly and required a lot of rests, went with us. It was great to have a place she could go to and have someone bring her coffee etc and hang out while the kids did more exploring in the parks.
If you have 4-5 people in the room, it can be a lot more reasonable to pay the extra money for concierge, but for a couple it isn't worth the extra cost unless you just like it.
For me, concierge is worth it when I have the extra money, when I will be in the hotel often and when it isn't a huge amount over regular rooms. I go to DL frequently and I enjoy resting in the hotel so that figures in for me. If I was in the park all day, I wouldn't bother with concierge. There is much better food for less money around the resort.