This one had been on this list for me to go to ever since I'd moved to Vegas last year. I'm generally hesitant to eat on the strip as it's sometimes tough to find the balance between the great food you're likely to find, but not overpaying for it.
L'Atalier isn't the priciest of places, nor the fanciest, but my experience here was amazing. The space is one of a kind... who would have thought that at a really nice place, you'll be sitting at a bar watching the kitchen? This really adds to the whole experience: you're not just getting a meal, you're watching a show.
The food here: also top notch and reasonably priced. I went with a fix price menu which consisted of 2 appetizers (mango ceviche, seared scallops) an entree (duck breast) and dessert (coffee ice cream) - sorry for not translating the dishes into food-speak for all you foodies out there, but I'll just write this review for the masses.
The waiter/bartender also brought us a foie gras with Parmesan foam small plate and a few desserts for our anniversary following the meal. As i went through course after course here... i can recall turning to my wife and saying "I feel like I'm on vacation". Yes, the food is just that good: some are a little unique modern flair that will be something you've likely never tried (Parmesan foam... foam??!), others are just the mark of a perfectly prepared and delivered classic dish (duck breast). Oh and potatoes Robuchon? Hands down best mashed potatoes i've ever had. The secret: 1 part potato... 2 (maybe 3?) parts butter. Sorry heart.
Definitely add to the list for a unique dining experience in Vegas. Hard to get out for under $200 if you're having any drinks though. IMO: worth every penny.