I bought a pair of the Columbia Switchback 2 Low trail shoes in March, and have taken them on a camping trip with several hikes.  They fit well, and have a very lightweight feel to them.  I say "feel" because they seem lighter than the 11-1/2 oz per shoe measurement (size 10) I got.  The outer sole has a deep tread pattern, good for trails. The shoes run normal size for a running/sports shoe (My size 10's give me about the same amount of room in the toe box as my size 10 Asics running shoes).

The hikes I've done in these shoes have all been 5 miles or more, and I carried a large hip pack with me. The shoes were very comfortable, and I wouldn't hesitate to wear them with a large pack. I don't do trail running, so I can't comment on that aspect of these shoes; but, if you don't need the ankle support of a boot, the Switchback 2 Low makes for a very comfortable and lightweight trail hiker.