Most of the wealthy people I know leveraged their house in their 20s/30s/(40s) but still paid their home early. I think the whole chicken or the egg thing is spot on. But then again around here most people I know have a 1000%+ return on their house. It is hard to see the downside of leverage when you are already paying 50-75% of your mortgage just to get in a house and you have 60% equity in a few short years. Definitely a unique area.
My own father was very opposed to prepaying a dime to the mortgage, but once they owed $40k or so they just paid it off. They most definitely leveraged when they were young and broke and 25 years into the thing they just paid it off. They are worth well over $1 mil. This is kind of my plan. I see no point in tying up my cash when I need it the most just so I can pay it off when I should have the cash to easily pay it off regardless. I still plan to have it paid off by 20 years but I don't see the point in prepaying a dime right now. So basically I do plan to do both myself.

If I wasn't so young though I would just prepay the mortgage. The long investment horizon makes all the difference.