We just spent the weekend at WDW (got back this afternoon) and the weather could not have been more perfect! Low 80s during the day and high 60s in the evening. Sunny, breezy, and gorgeous--plenty warm to swim but not too brutally hot to walk in the parks.
The Food and Wine Festival is SO much fun. This is the 3rd year in a row we've gone. There are booths set up all along the World Showcase with little samples of food for about $1.50 to $3.50, and wine, champagne, and beer from about $2.00 to $8.00 (there's always softdrinks if you don't drink alcohol). The atmosphere is very festive, everybody is friendly and smiling, and there's entertainment (musical bands, acrobats, jugglers, etc.) regualarly scheduled throughout the World Showcase.
If you don't mind waiting in line, there are free cooking seminars, wine tastings, tea tasting, etc. (we attended a Twinings tea tasting this year!). There are also numerous ticketed events ($$) such as wines paired with dinners.
There are pretty big crowds on Saturdays but the crowds aren't bad at all on other days of the week (and as I've mentioned in other threads, the crowds are never as bad as at the Magic Kingdom on Saturdays

).