If you sit at the bar, then you have access to a $6 burger+fries special (up from $5 a year or two ago). Which is a darn good deal in this economy.
No charge to sub bleu cheese...
Fries are pretty delicious, and the burgers are tasty and well-seasoned. Also, they grill their buns ever so slightly... mmmmmm.
I went there once for the Sunday brunch, however: not impressed. Every time we ordered - from the omelet to the fritata - was really plain, no flavor. Like stuff I make at home (ha). So I've shied away from ordering off the full menu since then.
The music, of course, makes the place. It's pricey: you have to buy tickets for a table, and THEN order food and drinks on top of that. BUT you can sit at the bar for free... and order a $6 burger :) The bar fills up pretty quickly though...