...and you are correct that US Airways is not included. You will need to search in the DL forum to see if there are exceptions or alternate programs for other carriers.
I just burned up my once in a lifetime Delta status match/challenge. I used the form on their website and e-mailed a copy of my credentials to the address provided. I simply included a copy of my US Platinum card and asked to be matched to the "equivalent level." It took over two weeks for me to get the confirmation/welcome e-mail and for my Delta status to be properly reflected.
So, long story short, they granted me Delta Platinum Medallion for my US Platinum which is contrary to what I've heard elsewhere but it does seem to be in line with the chart provided on their website for AA/UA. I seem to remember someone saying that a US Platinum would get Gold Medallion but if that's the case, I was either lucky or they changed their minds.