If you're a Facebooking birder (and not everyone is) with an interest in how this new social media world applies to rarity finding, the American Birding Association has created a new Facebook group dedicated to the sharing and discussion of rarities from the ABA Area and Hawaii.
Birders from all over the continent, and indeed the world, are welcome to join and contribute. In fact, the more members we have from across North America, the better the group will be at monitoring vagrant occurance across the continent. The group is called ABA Rare Bird Alert.
So come join 900+ fellow North American birders as we revel in rarities and live vicariously through vagrants across the continent at ABA Rare Bird Alert!