According to the current Win Share standings (from Major League Baseball Graphs-Thanks Murray), here is what the All-Star teams should look like (with Win Shares in parentheses):

American League

Starters

Jorge Posada, C (12.78)
Carlos Delgado, 1B (20.80)
Bret Boone, 2B (16.49)
Nomar Garciaparra, SS (15.79)
Corey Koskie, 3B (14.28)
Manny Ramirez, LF (14.18)
Mikeameron, CF (14.65)
Ichiro Suzuki, RF (14.47)
Edgar Martinez, DH (11.24)
Esteben Loaiza, P (15.55)

Reserves
(All players with 12 or more WS or 2nd in WS at their position, except DH, which is not a position)

A.J. Pierzynski, C (10.74)
Jason Giambi, 1B (16.23)
Mike Sweeney, 1B (11.74)
Alfonso Soriano, 2B (15.31)
Alex Rodriguez, SS (12.03)
Bill Mueller, 3B (9.94)
Eric Byrnes, OF (13.97)
Vernon Wells, OF (13.77)
G Anderson, OF (13.58)
Melvin Mora, (13.28)
Milton Bradley, OF (12.44)
Carlos Beltran, OF (11.70)
Mark Mulder, P (10.94)
Tim Hudson, P (10.84)
Roy Halladay, P (10.04)
Jamie Moyer, P (9.82)
Keith Foulke, P (9.72)
David Wells, P (9.60)
Barry Zito, P (9.49)
Mike Mussina, P (9.33)
Gil Meche, P (9.31)
Roger Clemens, P (8.94)

National League

Starters

Javy Lopez, C (13.65)
Todd Helton, 1B (14.38)
Jose Vidro, 2B (13.28)
Rafael Furcal, SS (13.43)
Mike Lowell, 3B (15.30)
Albert Pujols, OF (18.92)
Barry Bonds , OF (18.26)
Gary Sheffield, OF (16.65)
Austin Kearns, DH (14.41)
Kevin Brown, P (13.55)

Reserves
(All players with 13 or more WS or 2nd in WS at their position, except DH, which is not a position)

Ivan Rodriguez, C (13.50)
Jim Thome, 1B (14.04)
Marcus Giles, 2B (12.06)
Alex Gonzalez, SS (FLA: 12.23)
Scot Rolen, 3B (12.88)
Aaron Boone, 3B (12.33)
Bobby Abreu, OF (14.07)
Andruw Jones, OF (13.93)
Luis Gonzalez, OF (13.53)
Jose Guillen, OF (13.17)
Jim Edmonds, OF (13.15)
Corey Patterson, OF (12.98)
Jason Schmidt, P (12.61)
Hideo Nomo, P (12.14)
Eric Gagne, P (11.86)
John Smoltz, P (11.60)
Mark Prior, P (10.31)
Russ Ortiz, P (10.25)
Kerry Wood, P (10.00)
Woody Williams, P (9.47)
Randy Wolf, P (9.00)
Shawn Chacon, P (8.90)

I'm not crazy about a number of those choices, but at least it's impartial.