Yep, I use that one sometimes. Also Cornell's project feederwatch[1] and allaboutbirds[2]. Cornell has a lot of love for bird studies.

I've been tempted to apply when their Ornithology Department had web/mobile job openings, but moving to Ithaca for it seems a bit too much for me, even for a hobby I enjoy.

[1] http://feederwatch.org

[2] http://allaboutbirds.org