According to the U.S. District Court website for the Northern District of California, Judge Vaughn Walker will issue his decision on Wednesday, Aug. 4 in the Proposition 8 trial:

On August 4, 2010, the court will issue its written order containing findings of fact and conclusions of law following the court trial held in January and June of this year. The order will be e-filed in the court’s Electronic Case Filing system, and will be immediately available thereafter through ECF and PACER. There will be no court proceeding associated with the publication of the order.

UPDATE: From the American Foundation for Equal Rights, which brought the lawsuit:

The federal court announced today that it will release its decision in the American Foundation for Equal Right’s landmark case, Perry v. Schwarzenegger, on Wednesday. Text “EQUAL” to 69866 to get a text message with the official decision on your mobile phone the moment the court releases its decision, or sign-up for an email alert at equalrightsfoundation.org. Join AFER on its Web site to watch a live press conference with our plaintiffs and co-counsels Ted Olson and David Boies following the release of the decision. As we receive news about the details of the release, AFER will update our Facebook and Twitter profiles, along with our Web site.

UPDATE NO. 2: According to Equality Across Texas, there will be a rally — win or lose — at 6 p.m. Wednesday at the Legacy of Love Monument, at Oak Lawn Avenue and Cedar Springs Road:

Bring signs, flags and LOUD voices!

The Dallas action is being led by C.D. Kirven with GetEqual Now. To help plan, promote, or sponsor the Dallas action, please email cdkirven@aol.com

UPDATE No. 3: The ruling is expected to be issued between 1 p.m. and 3 p.m. Pacific time, which is 3 p.m. and 5 p.m. Dallas time.
UPDATE No. 4: The anti-marriage equality folks have filed a motion seeking a stay if Judge Walker strikes down Prop 8. Such a stay would presumably mean that same-sex marriages could not be performed pending the appeal of Walker’s decision. Our sources indicate that it’s likely Walker will grant this stay. If he strikes down Prop 8 and doesn’t grant the stay, the anti-gay marriage side would immediately request a stay from the appeals court, which also would likely be granted. In other words, it’s unlikely that marriages will be performed Wednesday or anytime in the near future.