I have had a Pine Warbler in my feeder all afternoon. He has been very entertaining to watch. He has a seed cracking method I didn't notice in the Pine Warbler that was at my feeder 3 years ago. He puts the Oil Sunflower seed in his beak and whacks the side of his beak real hard onto the feeder or deck railing to open it up. Real cool to watch. He also spent allot of time in my yard and my neighbors yard picking thru the grass. He should have been a Chipping Sparrow.
On that note, I hope that they should be back to my yard real soon as well. 
I took a nice photo of the Pine Warbler today if anyone is interested. 
Sean McCandless
Elkton, MD