I was having the same problem and it was only when I read this page that I realized what caused it.
to anyone who still needs a fix, you can download the version prior to the one available currently at
http://wl.dlservice.microsoft.com/download/E/3/E/...en/wlsetup-all.exe
uninstall all component of Windows Live Essentials and then run that file to replace them.
after you do this the 'send webcam' option will be available to you once more.
as far as I know there is no other work around - please correct me if I am wrong.