A jubilent Mayor Anthony Williams announced today at the City Museum that the Montreal Expos would indeed move to Washington D.C. next year. The Post has the story, as well as the Associated Press and Reuters.(Meanwhile, bitter Virginians are blaming their governor.)

According to the plan announced, the Expos first home game would be on April 15, 2005 in RFK Stadium, where the as-of-now-unnamed team would play for three seasons while a $400 million stadium was constructed along the Anacostia River near the Navy Yard Metro station. The stadium will be paid for using new business taxes.

The announcement comes several days of negotiations with Baltimore Orioles owner Peter G. Angelos about a compensation package that would “give Angelos certain financial guarantees”. According to the Post, Major League Baseball has proposed the following:

The three-pronged proposal calls for the Orioles’ participation in a regional sports network together with the Washington team; for baseball to make up for any revenue shortfall the Orioles might suffer because of the new team; and for baseball to also guarantee the Orioles’ value will not decline below a certain level in the event of a sale. Baseball would make up the difference, according to people familiar with the negotiations. … Angelos reportedly wants the financial guarantees to be effective indefinitely, while baseball wants the guarantees to last only as long as Angelos owns the team.

The AP notes that at today’s announcement, a petition was circulated to name the team after the Homestead Grays, a Negro League team that played in Washington in the 1930s and 1940s. The Grays was one of many to surface during a highly successful DCist naming competition earlier today.

See more DCist on baseball in D.C.: at least one group opposes using tax money to construct the stadium, read more about the proposed site and financing scheme,