> Where exactly on that map is the MIC?
MIC is currently under construction, slated for completion in 2012. It's located north of the Melreese Golf Course on the Google map, bounded by the canal on the south, SR953/NW42 Ave/LeJeune Road on the west (the road the purple marker actually follows), NW 37th Avenue on the east, and its northern boundary is a few blocks north of the canal (not sure exactly where).
You can read all about it at
http://micdot.com (the rail-specific part is "Miami Central Station").
As far as whether or not Miami's station should be downtown, at this point it's academic. MIC is funded and under construction right now. Having spent an unholy amount of money to build MIC at the airport, FDOT isn't going to pay to build another facility like it downtown (Orlando is next in line, and I'll be shocked if Tallahassee, Jacksonville, and Tampa haven't been coming up with their own projects to match it). Without FDOT funding, a station downtown won't happen. Miami (the City of) can't afford to do it on its own, and the county is loath to fund anything located in the City of Miami.
Politically, MIC's location is highly strategic. It lies at the western edge of the City of Miami, but is less than 2 miles north and southeast of downtown Coral Gables and downtown Hialeah. People can argue about the relative importance of Miami, Miami Beach, Coral Gables, and Hialeah, but basically Hialeah is #2 by population, and Coral Gables is #2 by downtown urbanity and total wealth (think: Beverly Hills vs Los Angeles).
If you look at
this Google Map, the location's choice might make a bit more sense. This map shows the location of MIC (just north of the golf course) relative to downtown Hialeah (marker "A") and downtown Coral Gables (marker "B"). MIC's train station will be located more or less where the 'train' icon (representing the current Airport Tri-Rail station) is located now. The main difference is that now, you have to take a shuttle bus to get to the station. When MIC is complete, there will be a peoplemover running between the airport terminal and MIC, and the new Metrorail station will be above it (the new Metrorail tracks are under construction now).
Even
if FDOT had the money and willingness to buy ROW, build/refurbish track, and build a new station downtown, I'd almost argue that the same money would be better spent extending the line west along CSX next to SR836, south alongside the Turnpike to the CSX ROW along SR874, then southwest to a new passenger station at the edge of Metrozoo along SW 152 St.
Approximate Route; A=MIC, B=Metrozoo Station. I might be wrong, but I think the building that housed the Gold Coast Railroad Museum (before Andrew destroyed it in 1992) at the site I'm describing actually
was a (minor) passenger rail station (serving the military base formerly on the site) until the 1940s.
Really, my biggest complaint about MIC is the fact that neither Dade County nor the City of Miami (I think both have jurisdiction over the area) have made any plans to enable (let alone encourage) high-value (but obviously low-height) commercial development surrounding what will ultimately be the most incredibly well-connected square kilometer of land in South Florida. As a result, the only major business establishment not related to the airport within walking distance of MIC on opening day is likely to be an adult superstore with 24/7 nude dancers -- the single most profitable business you CAN put into repurposed warehouses in an area zoned only for 'industrial' uses (which happens to include 'nightclubs', since industrial areas are one of the few places new nightclubs can go without causing noise and parking problems to surrounding businesses and residents).