Meh. They change it up every year, but their metrics appear to be more political than based on any sort of risk-based analysis or active efforts to protect them. The same handful of rivers <really> should show up on the list year after year.
FWIW, I tried something new a few weeks back. I drew a drainage map of the state of Tennessee on a white board and asked the class (upper-level undergrads) how many rivers they could accurately identify. The most anybody got correct was three. I was appalled. Guess the little signs telling you you're crossing into a new watershed aren't having their intended effect!
...and they're going to see that drainage map again towards the end of the semester.
