Selecting items in web mail

It's interesting to examine the various approaches web mail applications use for selecting multiple items (messages) in a list.

Yahoo mail provides check boxes but also lets users use Shift + Click and Ctrl + Click--the way you would multiple-select items in a desktop application. Regardless of how the selection is made, the item is both highlighted and its check box is checked:

Windows Live Mail uses the identical approach, except the check boxes for individual messages aren't visible until you roll your mouse over an item (or select it):

Gmail relies on check boxes, but it also provides links that allow you to make selections based on the message state (read, unread, starred, etc). Shift + Click and Ctrl + Click don't work in Gmail, however.

.Mac mail dispenses with the check boxes all together and  relies exclusively on  Shift + Click and Ctrl + Click for selecting multiple messages.