As of Wednesday, a Delta-Northwest match still wasn't a done deal. There is always the chance that Anderson will tell his board he thinks Delta should remain independent. That was the position taken by the Atlanta carrier's previous CEO, Jerry Grinstein, when the company was repelling a hostile takeover attempt by US Airways Group Inc. last year. There also is a possibility that Delta still could veer towards a United tie-up, and the two have continued exploratory talks over the past month, say multiple people briefed on the matter.