I am definitely "pro-bar" when it comes to eating dinner out. Sitting at the bar, you generally get a great view of the inner-workings of the restaurant, a chance to converse with other patrons, quick refills on those "adult" beverages, and, in my opinion, some of the best service available. At several of my favorite places in town I have barely graced a seat in the dining area - always opting for a comfy bar-side stool.
I like eating at the bar at Citronelle (and lobster-burgers when available!), the bar at Corduroy, the bar at Eve, and the bar at Dino (Chris is fantastic!)
For special occasions, its to the tables, but on your regular everyday dinner out, the bar is hard to beat!