For me, the trend has been to go ever lighter in recent years. On any kind of maintained trail, it is running shoes all the way. These days, I am wearing a pair of Asics Gel-Kahana 2's. I wore them on a 2-nite GC backpacking trip last month, and they were great! I don't know how I would feel about them on a 20+ dayhike. I used to do at least one R2R hike a year, but haven't for a few years because none of my current hiking companions are that serious. I want to do one this fall, and it will be in running shoes.
Back in the "old days", I wore heavy boots like most people. I still do occasionally if I anticipate extreme conditions. I used to swear by Raichle's, but then they started getting harder to find. Around 2001/2002, I bought a pair of Asolo Cerro Torre GTX's. In 2003, when they were starting to show some wear, I decided I liked them enough to get another pair. Unfortunately, they had been discontinued, but I finally found some online, in the right size and on clearance from Peter Glenn. They only had 2 pairs left, so I bought both. I only just now pulled the last pair out of the box, still new. I still have the original pair - the soles are almost smooth, and are worn clear through at the toes, but they are still in one piece and I have used them on occasion for heavy yard work. I think it is time to retire them for good, demote pair #2 to yard work, and start wearing pair #3 for hiking when conditions call for them.
For sandals, I used to wear Teva's, but now have a pair of Keen's with the enclosed toes. I like them OK, but use them only occasionally, mostly around water (like Aravaipa).