We have a 3 main domains that are all in a similar field, but have very distinct and separate subject matters. The domains rank well in their subject matter within that field, however recently we have seen a little slip in rankings. Onpage SEO and inbound link, etc.. are all pretty much the same - the one main difference is that about 1.5 to 2 years ago - we merged all the social media channels for those 3 domains into one central channel. So that each domain does not have its own FB, Twitter of G+ channels, they all use the same core channel.
With social factors becoming more important - was this a good move? Should we split them back out into their own channels again? Thoughts and input would be appreciated.