Dave posted some pictures of birds today and reported having difficulty telling a bird from a Meerkat. I don't wish to speak out of turn but suspect that his social life may be somewhat diminished by this inability. He should join the Foreign Birds Society and adopt a Cheeky Girl like my hero Lembit Opik. A little Chickadee would perk him up a treat, although he'd be well advised to steer clear of the Thrush.
I must admit that we occasionally have a problem telling Lily, our PBGV, from a Meerkat but find this instructional video quite useful: