The Delphi Magazine has announced in a letter to all subscribers, sent along with the December 2006 issue, that:
the March 2007 magazine (Issue 139) will be the last full issue to be produced. We may be able to produce some more articles after this date, but we cannot promise to do so, and they won't be in the form of full magazine issues.
As Dr. Bob (one of the most prolific The Delphi Magazine writers) mentions in his blog, he expects to write some more articles in the coming months and the magazine is actually offering a (rather cheap) online only subscription. You can find Julian Bucknall's opinion here: he's another devoted writer of the magazine. For many reasons I ended up writing for them only occasionally over the years... but I was (and I still am) an avid reader... too bad this has to end.
Good Luck, Chris Frizelle, and good bye, The Delphi Magazine.