If you are looking at the Holiday Inn near the Waterfront, it is coincidentally next to the Cullinan. Neither is actually AT the Waterfront, but just a few minutes away. They serve the Convention Center primarily. No shortcomings with either hotel that I know of. Perhaps you found these web sites:
http://www.southernsun.com/Sunrise/Hotels/CDA/
HTL_Index2/0,1997,10-73...
http://www.southernsun.com/Sunrise/Hotels/CDA/
HTL_Index2/0,1997,10-5-...
Neither lists high-speed internet service on their web sites. Just call them and ask them.