Ticketmaster added some more dates and when presales and sales start.
The Fillmore (Detroit, MI)
Fri, 06/22/12 at 07:00 PM
presale begins: Wed, 04/18/12 at 10:00 AM
Taft Theatre (Cincinnati, OH)
Mon, 06/25/12 at 07:30 PM
presale begins: Tue, 04/17/12 at 10:00 AM
State Theatre (Minneapolis, MN)
Wed, 06/27/12 at 07:30 PM
presale begins:Thu, 04/19/12 at10:00 AM
The Warfield (San Francisco, CA)
Sun, 07/01/12 at 08:00 PM
on sale: Fri, 04/20/12 at10:00 AM
Abraham Chavez Theatre (El Paso, TX)
Thu, 07/05/12 at 07:30 PM
presale begins:Tue, 04/17/12 at 10:00 AM
Majestic Theatre San Antonio (San Antonio, TX)
Fri, 07/06/12 at 07:30 PM
presale begins:Tue, 04/17/12 at 10:00 AM
Looks like the Cincinnati, and Minneapolis shows were listed a day early from what Dream Theater listed.