We need a coinbase like exchange for bitUSD to USD and other fiat first. I would love to do this, although, beyond registering as a Money Business and maintaining compliance in my state and with FinCEN, I have no clue how to create a website for that.
An exchange that stores and handles fiat USD has too much work to do. I believe bitUSD is more suitable for peer to peer transactions. Developing a peer-2-peer transaction site will be helpful, or simply contact localbitcoins.com to see if they can add bitUSD.
The reasons why localbitcoins is not widely used, from what I believe, are the bitcoin price fluctuation and the time needed to complete transaction. Using such a service you can't expect to complete transaction in real time, and at the time transaction ends bitcoin price can be far from what was initially negotiated, thus always making it unfavorable to one party. bitUSD doesn't have fluctuation problem and should be suitable for peer-2-peer trades.
Another drawback for fiat is bank transfer delay. We should think about providing bitBTC/BTC trading so that a peer-2-peer transaction may be completed much more rapidly.