Ok, we've searched EVERYwhere for this bird, and we can't seem to find it! Maybe someone can help us with my description only.
For 2 days in a row, he was WAY up in the tree singing his song. DH says he looks similar to a northern mockingbird (long tail, basically grey and white overall, about robin-sized as far as height), but a) we haven't heard any other calls from him as mockingbirds tend to do...and we've heard them in the recent past, and b) if by some chance it IS a mocker, what the heck could he be imitating?!
The song starts out slow, no rise or fall, one syllable that sounds like "teet", then speeds up. Like, "teet...teet...teet teet teet-teet-teet-teet, etc." Over and over. The only thing similar we could find was the song of the vermilion flycather, but it's far too high-pitched.
Sure hope you all have some suggestions for us! Would love to ID this "new" bird.