Miami's skyline is very impressive, but it's not DT/Brickell residents or their increased density that keeps Bayside open. Bayside is strictly tourists and cruise goers, event-goers, and people from other parts of Miami area. The success story with Bayside is actually how the owners and the city have kept it relevant and integrated it with with an overall larger package that makes for a nice visit with things to do.
Miami's Brickell and DT density is impressive, but I think a lot of people and urbanists in particular still sneer at the design that still frequently occurs where many of the towers are essentially vertical gated communities and don't properly integrate into the street. Like Chicago and Atlanta, there is a sea of parking pedestals as well with retail occasionally and only semi-decently added for people...though Chicago doesn't necessarily have a "problem" with this as it's about as good for pedestrians as one can get.
Finally, the other big thing with Miami is that many of these residents are part-time. Lots of the new condos are savings banks for Latins and they aren't necessarily all rented out to young professionals either. Lots of the proposed shopping (Miami World Center and Brickell City Centre) is enclosed and geared towards upscale visitors rather than locals and young professionals living DT. For people who visit and are accustomed to such large downtowns, it is notable the *lack* of pedestrian activity in Brickell/DT. Midtown Atlanta is far less dense, but seems far more lively in terms of offerings for those who want the downtown environment, and that is because of multiple factors (employment, history, integration of pedestrians into the built environment, which itself is mixed-density and offers more for people who actually want to live, work, and play in the area).
Miami's changing so quickly, but in my young circles, it's still not on the list of cities that college grads from the NE go to (neither is Atlanta/Charlotte for the most part, but they are much more of a destination). It's telling the lack
of office space in the nation's 3rd largest "skyline" (14.5 million SF leasable space between DT and Brickell, and less than 20 million SF overall with all of the government buildings...less than 2x the size of little ol' DT Jax in this regard).
I don't personally think downtown Miami will be much for the average young professional or visitor such as myself until it gets more office space built and more of a reason for being (as opposed to a sea of half empty condos owned by Brazilians and Argentinians with domestic currency issues and who enjoy brand name shopping elsewhere in Miami...which is the whole reason Brickell City Centre and Miami World are being built - not for permanent DT residents, but to keep these Latins convenient to their condos!). And while I acknowledge that Miami's downtown now has more buildings >400 ft than any other downtown in the US beside NYC and Chicago, it to me is still not the "3rd skyline" of America. It lacks the cohesion, architecture (perhaps even height), and history that other imo better skylines have with similar sizes as Miami's.
Great pictures though! Here's some more that I took one trip...
A suite inside the JW Marriott Marquis (I was impressed enough to take pics! heh):
