The Lean & Kanban 2009 conference which I promoted (am am speaking at) has been rescheduled to May 6-8. Its still in the same location in Miami, and the schedule is pretty much the same, although Don Reinertsen is unable to make it. There are early mutterings of a European based version of the conference towards the end of this year, so hopefully he might be able to attend that instead. The hope is that postponing the dates will allow more people to be able to attend.
Details of the conference can still be found at http://leankanbanconference.com/