score:5
1st UPDATE:
I got my visa from Chennai consulate in India today. They neither called my host nor me during these 3 days. So, this does imply consulates do accept AirBNB if proof is submitted along.
2nd UPDATE:
Just got back from Russia. I was asked to show proof of accommodation at the border control while entering the Russian Federation. He saw that and stamped me in. No further questions asked.