As of 2010-10-13.

Fx nightly Cr 8.0.552.0 Saf 5.0.2 Op 10.63 IE9b
HTMLCollection (unsigned long) no yes yes yes yes
HTMLCollection (DOMString) no yes yes yes yes
HTMLAllCollection (unsigned long) no1 yes yes yes yes
HTMLAllCollection (DOMString) no (yes in quirks) yes yes yes yes
HTMLFormControlsCollection (unsigned long) no yes yes yes yes
HTMLFormControlsCollection (DOMString) no yes yes yes yes
HTMLOptionsCollection (unsigned long) no yes yes yes yes
HTMLOptionsCollection (DOMString) no yes yes yes no (yes in quirks mode)
HTMLFormElement (unsigned long) no no no no yes
HTMLFormElement (DOMString) no no no no yes

1. document.all(unsigned int) succeeds quirks mode but returns undefined.