Agreed, I always double check that the browser password manager works, but it's tricky because there is no standard around what the fields should be called to make it always work. The best way to make sure it works is to put the username directly above the password in the same form, that will result in most password managers working, and this is especially important on registration forms.
Also for those that don't know why hunter2 was used above, enjoy! http://i0.kym-cdn.com/photos/images/original/001/065/965/989...