I went here a few weeks ago with my wife and mother. Food and service were good but not amazing. Compared to other neighborhood restaurants in Vegas, Rosemary's is certainly near the top. However there are much better restaurants on the strip in the same price range as long as you're willing to deal with traffic and parking to visit them. Bouchon I'm thinking of you.
I highly recommend trying their beer pairings with whatever dish you have. The wine list is your standard fair but the beer list extensive and one of the best I've seen in a while.
Keep an eye out for specials. Some of their deals (25% off and up) can make Rosemary's a real bargain.