Today I went on a 4 mile hike with the wife and kids. I was carrying my daughter in our baby pack(she weighs more than my 3 day pack) I didn't feel like wearing my hiking boots so I just wore my Nike Pegasus running shoes and really enjoyed a day without the weight of boots. This got me thinking about switching to just wearing running shoes on light trips.

Now the question is, what are the differences between standard running shoes and "trailrunners" (I have never owned a pair) I expect that the soles may be more rigid, but are there any more improvements to make them a better choice and make me fork over the cheddar.

Sean