The heron must not eat at SNOB very often, they can rarely accomodate a 6 top, unless you rent the entire restaurant. The food isn't what it used to be anyway, try Magnolias upstairs for private dining.
you could also try McCrady's - i hear their private room is really nice. also, went to a dinner for about 30 people at Cypress earlier this week - also a good choice.
Thanks for the recs - we ended up at Cru Cafe as they could take 30 that included the upstairs private room that held 21. Great food, reasonably priced - lots of fun sitting at the high table looking into the kitchen!!