Vanity Fair Portraits 1913 - 2008.
You'll see all the usual suspects but the thing I found most interesting was the crowd. It was pretty packed when I was there and it was right at the end of the day as well. I was surprised that a photo show could generate so much interest in these days of "everything happens on the web".
You can find out more at ... http://www.rom.on.ca/exhibitions/special/vanityfair/index.php