I spectated the 2005 US Am at Merion and to me it is really a unique course. IHMO super cool that the US Open will be there.
I'm actually quite certain that it will be easier for them to set it up as a Par 70 such that they have a "US Open" tough course (and no -20 scores) compared to the difficulties of having enough room for spectators both on the course and parking.
I plan on taking the whole week off from work.
http://www.usamateur.org/2005/index.html
you can click through to the photo gallery.
I like the wicker basket flag sticks, pretty cool IHMO.