Well, let's see...
Here are boxscores from the North American leg of Madonna's Confessions tour in 2006:
The Forum Los Angeles 40,044 / 40,044 (sellout) $7,686,380
MGM Grand Garden Las Vegas 27,528 / 27,528 (sellout) $7,257,750
HP Pavilion at San Jose San Jose 27,024 / 27,024 (sellout) $4,761,555
Staples Center Los Angeles 14,158 / 14,158 (sellout) $2,804,583
Save Mart Center Fresno 20,154 / 20,154 (sellout) $3,749,800
Glendale Arena Phoenix 28,820 / 28,820 (sellout) $4,890,090
United Center Chicago 52,000 / 52,000 (sellout) $9,271,790
Bell Centre Montreal 34,940 / 34,940 (sellout) $5,670,150
Hartford Civic Center Hartford 21,558 / 21,558 (sellout) $3,451,235
Madison Square Garden New York 91,841 / 91,841 (sellout) $16,507,855
TD Banknorth Garden Boston 36,741 / 36,741 (sellout) $6,337,115
Wachovia Center Philadelphia 29,749 / 29,749 (sellout) $4,639,775
Boardwalk Hall Atlantic City 12,322 / 12,322 (sellout) $3,246,100
American Airlines Arena Miami 30,410 / 30,410 (sellout) $5,568,485
Well, here are U2's boxscore results from 2005 in North America:
1ST LEG of VERTIGO WORLD TOUR: NORTH AMERICA
1, 2. San Diego, California : March 28, 30, 2005 : ipayOne Center at the Sports Arena : GROSS $2,909,029 : ATTENDANCE 29,140 : SHOWS 2 : SELLOUTS 2
3, 4. Anaheim, California : April 1-2, 2005 : Arrowhead Pond : GROSS $3,454,198 : ATTENDANCE 33,535 : SHOWS 2 : SELLOUTS 2
5, 6. Los Angeles, California : April 5-6, 2005 : Staples Center : GROSS $3,673,850 : ATTENDANCE 34,527 : SHOWS 2 : SELLOUTS 2
7, 8. San Jose, California : April 9-10, 2005 : HP Pavillion : GROSS $3,357,098 : ATTENDANCE 36,140 : SHOWS 2 : SELLOUTS 2
9, 10. Glendale, Arizona : April 14-15, 2005 : Glendale Arena : GROSS $3,198,861 : ATTENDANCE 34,905 : SHOWS 2 : SELLOUTS 2
11, 12. Denver Colorado : April 20-21, 2005 : Pepsi Center : GROSS $3,509,741 : ATTENDANCE 36,714 : SHOWS 2 : SELLOUTS 2
13, 14. Seattle, Washington : April 24-25, 2005 : Key Arena : GROSS $3,105,574 : ATTENDANCE 30,251 : SHOWS 2 : SELLOUTS 2
15, 16. Vancouver, British Columbia : April 28-29, 2005 : General Motors Place : GROSS $3,020,466 : ATTENDANCE 37,031 : SHOWS 2 : SELLOUTS 2
17, 18, 19, 20. Chicago, Illinois : May 7-12, 2005 : United Center : GROSS $7,541,679 : ATTENDANCE 77,173 : SHOWS 4 : SELLOUTS 4
21, 25. Philadelphia, Pennsylvania : May 14-22, 2005 : Wachovia Center : GROSS $3,767,178 : ATTENDANCE 39,273 : SHOWS 2 : SELLOUTS 2
22, 23. East Rutherford, New Jersey : May 17-18, 2005 : Continental Airlines Arena : GROSS $3,838,066 : ATTENDANCE 40,347 : SHOWS 2 : SELLOUTS 2
24. New York, New York : May 21, 2005 : Madison Square Garden : GROSS $1,907,086 : ATTENDANCE 18,415 : SHOWS 1 : SELLOUTS 1
26, 27, 28. Boston, Mass. : May 24, 26, 28, 2005 : FleetCenter : GROSS $5,071,565 : ATTENDANCE 51,658 : SHOWS 3 : SELLOUTS 3
1ST LEG of VERTIGO WORLD TOUR TOTALS
GROSS: $48,354,391
ATTENDANCE: 499,109
AVERAGE GROSS PER SHOW: $1,726,942.5
AVERAGE ATTENDANCE PER SHOW: 17,825
AVERAGE TICKET PRICE: $96.88
SHOWS: 28
SELLOUTS: 28
3RD LEG OF VERTIGO WORLD TOUR: NORTH AMERICA
61, 62, 63, 64. Toronto, Ontario : Sept. 12, 14, 16-17, 2005 : Air Canada Centre : GROSS $7,624,870 : ATTENDANCE 82,572 : SHOWS 4 : SELLOUTS 4
65, 66. Chicago, Illinois : Sept. 20-21, 2005 : United Center : GROSS $3,795,583 : ATTENDANCE 38,815 : SHOWS 2 : SELLOUTS 2
67. Minneapolis, Minn. : Sept. 23, 2005 : Target Center : GROSS $1,823,883 : ATTENDANCE 19,328 : SHOWS 1 : SELLOUTS 1
68. Milwaukee, Wis. : Sept. 25, 2005 : Bradley Center : GROSS $1,782,895 : ATTENDANCE 19,336 : SHOWS 1 : SELLOUTS 1
69, 70. Boston, Mass. : October 3-4, 2005 : TD Banknorth Garden : GROSS $3,381,429 : ATTENDANCE 34,488 : SHOWS 2 : SELLOUTS 2
71, 72, 73, 74, 75. New York, N.Y. : Oct. 7-8, 10-11, 14, 2005 : Madison Square Garden : GROSS $9,658,009 : ATTENDANCE 93,275 : SHOWS 5 : SELLOUTS 5
76, 77. Philadelphia, PA : Oct. 16-17, 2005 : Wachovia Center : GROSS $3,773,053 : ATTENDANCE 39,305 : SHOWS 2 : SELLOUTS 2
78, 79. Washington, D.C. : Oct. 19-20, 2005 : MCI Center : GROSS $3,902,569 : ATTENDANCE 38,181 : SHOWS 2 : SELLOUTS 2
80. Pittsburgh, PA : Oct. 22, 2005 : Melon Arena : GROSS $1,636,798 : ATTENDANCE 16,899 : SHOWS 1 : SELLOUTS 1
81, 82. Auburn Hills, Mich. : Oct. 24-25, 2005 : Palace of Auburn Hills : GROSS $3,951,103 : ATTENDANCE 41,379 : SHOWS 2 : SELLOUTS 2
83. Houston, TX : Oct. 28, 2005 : Toyota Center : GROSS $1,652,699 : ATTENDANCE 17,002 : SHOWS 1 : SELLOUTS 1
84. Dallas, TX : Oct. 29, 2005 : American Airlines Center : GROSS $1,689,471 : ATTENDANCE 17,988 : SHOWS 1 : SELLOUTS 1
85, 86. Los Angeles, Calif. : Nov. 1-2, 2005 : Staples Center : GROSS $3,656,978 : ATTENDANCE 34,291 : SHOWS 2 : SELLOUTS 2
87, 88. Las Vegas, Nev. : Nov. 4-5, 2005 : MGM Grand Garden : GROSS $3,864,843 : ATTENDANCE 31,863 : SHOWS 2 : SELLOUTS 2
89, 90. Oakland, Calif. : Nov. 8-9, 2005 : Oakland Arena : GROSS $3,638,620 : ATTENDANCE 36,340 : SHOWS 2 : SELLOUTS 2
91, 92. Miami, Fla. : Nov. 13-14, 2005 : American Airlines Arena : GROSS $3,589,942 : ATTENDANCE 37,354 : SHOWS 2 : SELLOUTS 2
93. Tampa, Fla. : Nov. 16, 2005 : St. Pete Times Forum : GROSS $1,825,243 : ATTENDANCE 19,354 : SHOWS 1 : SELLOUTS 1
94, 95. Atlanta, Ga. : Nov. 18-19, 2005 : Philips Arena : GROSS $3,500,572 : ATTENDANCE 36,334 : SHOWS 2 : SELLOUTS 2
96, 97. New York, N.Y. : Nov. 21-22, 2005 : Madison Square Garden : GROSS $3,859,828 : ATTENDANCE 37,314 : SHOWS 2 : SELLOUTS 2
98. Ottawa : Nov. 25, 2005 : Corel Centre : GROSS $1,486,710 : ATTENDANCE 18,647 : SHOWS 1 : SELLOUTS 1
99, 100. Montreal, Quebec : Nov. 26, 28, 2005 : Bell Centre : GROSS $3,575,491 : ATTENDANCE 43,294 : SHOWS 2 : SELLOUTS 2
101, 102. Boston, Mass. : Dec. 4-5, 2005 : TD Banknorth Garden : GROSS $3,400,861 : ATTENDANCE 34,583 : SHOWS 2 : SELLOUTS 2
103. Hartford, Conn. : Dec. 7, 2005 : Hartford Civic Center : GROSS $1,542,471 : ATTENDANCE 16,165 : SHOWS 1 : SELLOUTS 1
104. Buffalo, N.Y. : Dec. 9, 2005 : HSBC Arena : GROSS $1,711,094 : ATTENDANCE 18,826 : SHOWS 1 : SELLOUTS 1
105. Cleveland, Ohio : Dec. 10, 2005 : Quicken Loans Arena : GROSS $1,791,497 : ATTENDANCE 19,765 : SHOWS 1 : SELLOUTS 1
106. Charlotte, N.C. : Dec. 12, 2005 : Charlotte Bobcats Arena : GROSS $1,672,440 : ATTENDANCE 17,804 : SHOWS 1 : SELLOUTS 1
107. St. Louis, Mo. : Dec. 14, 2005 : Savvis Center : GROSS $1,839,020 : ATTENDANCE 19,923 : SHOWS 1 : SELLOUTS 1
108. Omaha, Nebraska : Dec. 15, 2005 : Qwest Center : GROSS $1,500,834 : ATTENDANCE 16,134 : SHOWS 1 : SELLOUTS 1
109. Salt Lake City, Utah : Dec. 17, 2005 : Delta Center : GROSS $1,709,317 : ATTENDANCE 18,197 : SHOWS 1 : SELLOUTS 1
110. Portland, Ore. : Dec. 19, 2005 : Rose Garden : GROSS $1,670,879 : ATTENDANCE 18,233 : SHOWS 1 : SELLOUTS 1
3RD LEG OF VERTIGO WORLD TOUR TOTALS TO DATE
GROSS: $90,509,002
ATTENDANCE: 936,975
AVERAGE GROSS PER SHOW: $1,810,180
AVERAGE ATTENDANCE PER SHOW: 18,740
AVERAGE TICKET PRICE: $97.01
SHOWS: 50
SELLOUTS: 50
As anyone can see, there is simply no comparison. U2 are way ahead in both gross and attendance in North America.