Comparing the old 70-300mm ED to the VR version.
VR vs. non-VR
$670 vs. $470
17e (2ED)/12g vs. 13e (1ED) /9g
loose a negligible 0.5f at the short end.
40% heavier (the existing one is pretty light anyway)
3cm longer & tiniest bit wider.
and it looks like they swapped the focus and tele ring(?)