By Lenn Thompson, Founder and Editor-in-Chief Miguel Martin, the Spanish-born winemaker who joined Palmer Vineyards just in time for the 2006 harvest, has already impressed with what he's done with the winery's white wine program, especially sauvignon blanc and blended whites. Those wines, of course, go from field to glass much more quickly than do reds. We've had to wait a big longer for those, but one of Martin's first reds, Palmer Vineyards 2006 Proprietor's Reserve Cabernet Franc ($25), impressed in a tasting earlier this week. 2006 wasn't a great year for reds on the North Fork. It was cooler…