I live next to City North and have been to Blue Martini on multiple occasions. Happy hour is the best time to go. The crowd is more of what you would expect for an upscale Scottsdale type establishment. (even though this is actually situated in North Phoenix).
The food is pretty great at the happy hour prices. Ranging from your flat breads to lamb chops. They have many martinis on the menu that are very tasty. (go figure, hence the name right). Wednesday is ladies night (also Cougar night) but Fridays/Saturdays are a more heavily ladened with cougars on the prowl and men cruising the scene ranging from your youngsters looking for a sugar mama and older men in there 50's/60's trying to dress as if they are still in there late 20's, early 30's.. Good place to people watch.