This is an American Goldfinch.

I know this only because I googled for yellow birds in New England.  I had never seen one before. However, for the past few days I have been seeing some bright yellow bird out of the corner of my eye.  I could never quite get a good look at it as it flitted by the house or swooped into the bushes.  Eventually, I decided that I was seeing a light-colored sparrow and the sun was playing tricks on my eyes.  Until today, however, when it landed on a fence post right next door.  I got a good look and then went to the computer to look it up.  To my surprise, these birds are considered quite common here and yet I have never seen one before in my life. 

Apparently, these birds often winter here in the cold north.  I am going to keep a lookout for them this winter and perhaps it will be a good time to start putting out birdseed.  This new location of ours has proved a wonderful spot for birdwatching.

More on the American Goldfinch: http://en.wikipedia.org/wiki/American_Goldfinch