Can someone explain those free 0.00000001 BTCs?

I’ve just noticed an odd transaction to my wallet address. 1LnNQDKV6DiMnZ2rZ9yXpcnnTh7my1WusP seems to be giving me a free 0.00000001 BTC.

Investigating further shows that I’m not the only one receiving the free 0.00000001 BTC. Take a look at the blockchain transaction.

What is happening? Is this guy using blockchain’s public note as an advertisement spam?