Friends? What are those?
Anyway - the concept is interesting. And if we look aside from the minor fact that Sothis probably would have to implement some kind of "referral id" the voters could use - I like the incentiv to get more people to vote.
Of course - the challenge is - and will always be - to get people to write some more or less well thought out recommendations. I know myself how hard that is.
But to summarize: I support everything that can help the anime recommendation database to grow - but I am uncertain what is the best way of doing this. I would perhaps suggest that it was created moderators for genres or studios etc. that could check the quality of the recommendations - just like you have in the forum.
And I believe also there might be an advantage with including some kind of additional information with the anime recommendations. Like for instance getting freakzilla or some other knowlegdeable user to write some indepth comments about particular anime studios, genres etc. - in other words - something that represents an added value to the user of the anime recommendation tool. Perhaps we could attract even more users to the recommendation tool. But then it would turn more and more into a kind of webzine I guess.
But it is at least a thought.