I work for an architectural firm, and we do a TON of multifamily work. (1000+ units a year) I don't do many single family homes unless thier huge.
Granite is nice - but seems to be losing some popularity.
We still see a lot of clients using laminate tops - for cost reasons.
I did laminate in my own home this spring - with a pretty high-end product, but it is laminate nonetheless. Link below
http://www.outdoorsmenforum.ca/showthread.php?t=134231
I don't have much exposure to quartz, but I hear good things. I'm doing a high-end golf course clubhouse and we're about to install quartz bar countertops - will be interested to see how it turns out.
For corian - some people really like it, but for me, I'm kinda meh about it.