If the stock is delisted by the exchange, it will pop up on another exchange (such as the pink sheets, which is where companies going through a bankruptcy are generally moved to). If, however, the SEC says the company can't be traded in the US, I can't say what happens. That is extremely unlikely with a major company like BIDU, though.
Was involved with a company buyout last year, resulting in a delisting. They froze the share price at current buyout price. Then you just "cash out" with cash in your account. That particular transaction took Apx 2 months! Your money is tied up. BIDU may be different, I have no clue! But once they pull the trigger, it's a done deal. What I would be worried about here is how much warning, if any, will we get? I'd be watching the news very closely.