Dancing grapevines greeted the arriving guests. The Hoopla Committee, wearing pineapple-shaped sun glasses, was handing out flowers. Vintner Judd Finklestein, playing his ukelele, led the vintners’ parade.

That was the scene at Friday’s Taste Napa Valley, where about 2,500 soaked up the flavor on the day before the Napa Valley Vintners’ Auction Napa Valley 2008.

The dancing grapevines were actually green-faced women on stilts from the Living Garden of Second Nature Productions, but their extraordinary contortions were just part of the dazzle of what’s possibly the biggest party in the valley. This is the community event where the visitors to the valley for the four-day auction mingle with valley folks —  local residents, vintners, restaurateurs and about 800 volunteers who help pull off this grand wine- and food-tasting at Trinchero Family Estates in St. Helena.

Oprah Winfrey was among the attendees, many of whom sampled cookies handed out by the French Laundry’s Thomas Keller (“the best shortbread this side of England”), meatballs made by Bistro Don Giovanni’s Donna Scala and crab cocktails created by Greg Cole and his team from Cole’s Chop House.

One could have passed the day sampling wines from vintners and tasting the excellent fare from valley restaurants, but inside Trinchero warehouses there was also serious business going on. The Vintners’ e-auction was coming to a close, and winemakers set up barrel tastings to accompany the bidding.

In a separate room, lavish displays showed off the auction lots that will go up for bid at Saturday night’s main event.

“There’s a lot of wow in here,” observed Spottswoode’s Mary Novak, strolling past the king’s ransom of fabled wines and embellishments, such as bejeweled sparkling wine bottles from Mumm or the L’Amour diamond pendant donated by Chanel, which will go to the high bidder of the Fund-a-Need lot.

But for all the wow factor, the underlying reason for all the festivity of Auction Napa Valley isn’t overlooked. Since the Napa Valley Vintners first hosted the auction since 1981, the event has raised $80 million for community charities.

“They’ve just given $2 million to schools. I think volunteering is the least I can do,” said Napa County Superintendent of Schools Barbara Nemko, who was working at the event.

Teacher Roberta Wright was another volunteer. “I’ve seen what this money does for the kids I teach,” Wright said. “It’s just amazing what comes back to us from it.”

A fewer bidders will attend the Saturday night auction, where one of the 44 fabulous lots includes a Lexus full of wine bottles. The most highly anticipated lot is the one celebrating the life of Robert Mondavi, who died May 16. A simple white memorial to Mondavi marked the entrance to the event, where guests could sign a memory book.

Correction: An earlier version of this article stated an incorrect amount raised by the auction since 1981