This is from the article that PeteinMiami provided:
The New South Terminal , with 27 gates and an adjoining cruise ship bus depot, a $1.1 billon dollar facility, starts operations in 2007. North Terminal, a $2.85 billion one mile long facility, has been partially completed and is in use by American Airlines and its “ Oneworld” alliance partners, and construction on the remainder of this 48 gate facility continues. Additional North Terminal gates will be phased-in operation periodically as construction is completed while the entire project progresses towards substantial completion in 2011.
THis is from Wikipedia:
Concourse J is a new concourse currently under construction and expected to open in August 2007 under Miami International Airport's South Terminal Renovation Project.  The Concourse was designed by Carlos Zapata of Studio Carlos Zapata in New York, with M.G.E., one of the largest Hispanic owned architecture firms in Florida, as the architect of record; the Concourse will hold Star Alliance and SkyTeam Members. Together with Concourses G and H, this area will be called the "South Terminal". It will be the only pier at the airport able to accept the new Airbus A380 and will introduce a third customs and immigration facility at the airport, supplementing the ones at Concourses B and E; with international SkyTeam and Star Alliance members moving to this new concourses, it is expected that the new facilities will ease overcrowding that has plagued the concourse E immigration facilities since new US entry laws came into effect.
Once the North and South Terminals are completed, all airlines not affiliated with either the Star Alliance, SkyTeam Alliance (South Terminal), or Oneworld (North Terminal) will be housed at the remaining Concourses E and F, this implementation has already begun at MIA
with airlines formerly housed at Concourse A but not part of Oneworld alliance having been moved to Concourses E and F.