As for extra dates in the US/Canada schedule, here's my guess. Extra dates in italics:
2010-06-06: Angel Stadium, Anaheim, California
2010-06-07, Anaheim (or on 2010-06-08)
2010-06-10, San Diego
2010-06-12: Invesco Field, Denver, Colorado
2010-06-13, Denver? I wouldn't have expected two, but maybe to make up for demand from Texas, et al.
2010-06-16: Oakland-Alameda County Coliseum, Oakland, California
2010-06-17: Oakland
2010-06-20: Qwest Field, Seattle, Washington
2010-06-23: Commonwealth Stadium, Edmonton, Alberta
2010-06-24, Edmonton
2010-06-27: Minneapolis
2010-06-30: Spartan Stadium, East Lansing, Michigan
2010-07-03: Rogers Centre, Toronto, Ontario
2010-07-06: Soldier Field, Chicago, Illinois
2010-07-09: Land Shark Stadium, Miami, Florida
2010-07-12: Lincoln Financial Field, Philadelphia, Pennsylvania
2010-07-13, Philadelphia
2010-07-16: Venue to be announced, Montreal, Quebec
2010-07-19: New Meadowlands Stadium, East Rutherford, New Jersey
2010-07-20: East Rutherford
That gap between Edmonton and East Lansing could conceivably fit two shows, not just one ... say Minneapolis and St Louis or Minneapolis and somewhere in Wisconsin. However, I don't expect there will be. If you look at the schedule, it seems the claw needs about 9 days at minimum to move between venues and be set up in time for the concert. If you squeezed two gigs in between Edmonton and East Lansing, that means Edmonton's claw would have to get to East Lansing in just six days. Don't see THAT happening.