Realized I never followed up with my experience at the Miami Hilton Downtown--
Overall, a great stay. I contacted the hotel in advance by email about any specifics regarding having a pet, they replied back that there was nothing special required like documentation of shots/vaccines, etc. There are no specific rooms for travelers with pets.
In fact, we were upgraded to a top-floor bay-view room with a stunning view of Miami, Biscayne Bay, and the cruise-ship terminal.
They provided a bed and food bowl for our dog, as well as a hangtag for the door indicating there was a pet in the room. Although we didn't do it, the hotel allows you to leave the dog in the room by itself for short periods. The hangtag will alert housekeeping not to enter the room.
The staff was very friendly, helpful and courteous.
Because I had just dropped to Silver from Diamond on 1 April, no internet or breakfast was provided.
Only 3 downsides of note:
1. Because the parking garage is all concrete, no grass, etc. you must take 2 elevators to reach street level for your dog to do its business. 1 elevator to the lobby level, then another 7 floors down to the street.
2. Staff had some coordination problems in locating a Fedex package that was sent to me during my stay; it took multiple phone calls and I had to personally go to street level to find the guy who had the package to sign for it. And got charged 5 bucks as a 'package handling fee'. Not a major issue, but still something of an annoyance.
3. Parking garage is not hotel-owned, but a commercial 3rd party. As such, no in-and-out privileges, and $25 per night. Valet would have in/out privileges, but would run at least $30+ with tax and tip. Valet not an option for us because of logistics issues with our dog.