Maybe this will actually be good enough that I won't find myself wishing I had time to write my own...
I do have my doubts about the dependency on eBird, though. Given that eBird = Cornell Lab of Ornithology = the top birders in the USA, linking up with eBird is obviously the right move from the branding standpoint, and the right move from the I-don't-want-to-piss-off-the-establishment standpoint. But from the user's standpoint? They claim that "participation in eBird has exploded in the last two years". Either they vastly improved the eBird interface or birders are a very stubborn and obsessive lot [1], because I looked at eBird a while back and it had one of the worst interfaces I had ever seen. Like, corporate internal Java application bad.
---
[1] Which is to say: I'm not convinced they've improved the interface.