Marriott has a lot of hotels with very slow internet. I know it costs money, but they need to address this as a major corporate issue. I don't know about other brands because I don't stay in them much, but as far as Marriott is concerned, this is indeed a major issue.
This is not a problem with Charlotte, it is worldwide and industry wide. I spend too many nights cursing at my computer because of the slow speeds provided by the hotels. My solution has been to walk my laptop to the nearest Starbucks and work from there for the things are are time sensitive. It is not just Marriott, it is everyone. I have complained to management, the "support" line and to anyone who will listen to no avail. I've begun looking at a wireless stick for my computer rather than taking advantage of the free internet at the hotels.