There's an interesting article on kitchen countertop materials in today's real estate section. [It's in the local paper, but reprinted from the South Florida Sun-Sentinel; it's by Charlyne Varkonyi.]
Granite is the first choice (its cost is competitive with quartz and Corian); quartz is second. Granite is cheaper in Florida than in the Northeast and Midwest, btw. At the very high end, some people want copper, concrete, or glass
Soapstone is for trophy kitchens and people who don't use them much. Quartz is best for easy maintenance. [I'll take it!] Granite and wood are pretty, but need more maintenance, and there are bacterial concerns. (Sanitize wood with vinegar and water.) Track down the article for the fine print.