The American Ornithological Union has published the 52nd supplement to the Checklist of North American Birds. This supplement includes a number of changes, most of which will not affect your list except for the order and a few splits. The splits result in new names but no gains to your list in Canada or the United States. The scientific name changes are mainly in the Wood Warblers and a few other changes in genus and family order. The only change that affects the Canadian/US bird list is the split of the Old World Common Moorhen from the New World population. The name Common Moorhen is now back to Common Gallinule. For a complete summary of the changes visit http://www.aou.org/auk/content/128/3/0600-0613.pdf.