New Bird!

We have a new bird at the feeder! Anyone know what he is? We call him Zorro because of his mask.
UPDATE: After doing research, I believe this is a Blue Tit. It is hard to see any blue on him in these shots, but I've come to this conclusion because of the stripe and song he makes. It seems we also have Great Tits coming to the feeder. Maybe I'll post a photo of one of them someday. But, for now, I have to get back to the shots I took while my friend, Rachel, was visiting. Thanks to Scott for sending me down the right road!