On March 27, 2012, there were several reports of the "first of the season" Phoebes in the Lehigh Valley of Pennsylvania.
In my records, in 2011, these first showed up in Kunkletown (north of the Kittatinny Ridge) on 3/23 and last year on 3/15. I haven't seen them here yet, but one was at the Lehigh Gap Nature Center yesterday (3/27). In 2012 (a wierd year, for sure), the first reports in the Lehigh Valley were on 3/11 and 3/13. I have the data for the Lehigh Valley in 2011, but not at my fingertips. They sometimes are quiet for the first week or so when they first arrive, so are less noticeable.