So... When should we be posting to all the different Social Media sites?

I've been doing a bit of research on this and have found the following site quite useful:

ADD THIS  - Content Engagement Made Simple.

Anytime someone shares, follows, or interacts with a piece of content, there's a good chance AddThis has something to do with it. According to comScore, we reach over 98% of the US — that's more than Facebook or Google. Our team is focused on building the best social tools, content recommendations and targeted advertisements. It's growing like crazy and we're proud to be the leader in content engagement.

Although an American site the information can be transferred across to the UK depending on your market.  So, my next plan is to make a schedule!