I was at Point Pelee a few weeks ago and several (apparently) knowlegable birders were calling White Crown Sparrows as Lincolns. They did look a bit different than our version (a bit larger, more upright, more of a crest on the head) and I have not seen a Lincoln's so I took their call at face value initially. When i checked the books, it was pretty obvious that these were not Lincolns. Now the Kirtlands Warbler was a 'for sure.'

Best,

Joe