Yahoo has added
some very useful filters to their Image Search engine. For instance,
you can specify dimensions (height x width) in the search query and it
will display only pictures / icons that exactly match your specified
size.

This means you can also use Yahoo! Images as an Icon Search Engine since icons are either 16×16 or 32×32 in size and this limit can be set at the time of search.

Then there’s a new "Recent Images" feature where you’ll find news related pictures that are fresh and have included only recently (like 2 hours ago).

And for people who hate to see so many pictures from Flickr included in Yahoo’s index, there’s a new option to let you restrict photo search to only-Flickr or absolutely-no-Flic