I agree that there are similarities between early Bon and Vajrayana as practised in TIbet but there are also great differences. Bon focused on sacrifice including animal sacrifice and appeasements of local deities. It does not agree with the core teachings of Buddhism which include compassion for all beings, emptiness, interdependence and buddha nature.
The great buddhsit master Milarepa had a confrontation with a Bon teacher at Mt Kailash and this is described here
http://www.kailashzone.org/pages/sit...mtlake/mt.html
Padmasambhava who is claimed to be the one who established Vajrayana in TIbet was one who did not agree with destroying others beiefs rather he would transform them into something beneficial and in tune with the dharma. So some aspects of BOn became associated with Vajaryana but without the harmful practices of animal sacrifice etc.
Modern day Bon is quite different and is said to originate from an earlier Buddha.. one many aeons before Shakyamuni.
Just to conclude i think that as interesting as this post has become it has perhaps hijacked the original post so apologies if this is so and feel free to move it if necessary.