Don't go. Really.
The food is adequate. The steak is a safe bet but you can get similar steaks in hundreds of places around the city. The last time I was there about 3 years ago the place still had all it's pay phones from the 1970s. The most exotic beer they served was Heineken. Are you getting the picture now? The place is a time warp.
If you're still determined to go, business casual would work just fine.
re: Bob Martinez
Here is my report from last night. The patrons were interesting..a very eclectic crowd of actors (Sopranos, Tony Danza, and even a drag queen). Very crowded and talked with Elaine herself. We all knew the food would not be good, but it was average. Appetizers were the shrimp cocktail, fried calamari, smoked salmon. Main course (I learned from a partron that you can just order and they will make it for you) was a grilled salmon with veggies, Pasta Primavera (not so good) and a risotto. Dessert was the creme brulee and the chocolate cheesecake. We had 2 bottles of wine and sambuca after the meal. All in all, I would NEVER run back for the food, but the overall environment made it fun.
I am DYING to hear your report. I went there once about 8 years ago, and the food was disastrous from start to finish. Drowned salads, stale bread. My poached salmon smelled so vile I had trouble sitting near it - eating it was out of the question. It was a group dinner and sending back food would have insulted the host. Wishing you much better luck.