The original idea started in 2006 while I was working with Eight Media, which I had founded together with Daniel Spronk (spazmaster). After hacking away at a prototype for a while we presented our MVP to a live audience in London in 2007. The response was overwhelming, we got serious about it. Found an angel willing to invest.
Then in 2009 Daniel went back to focus on Eight.nl while I kept going with Soocial. Looking back I think it was much harder without Daniel as a co-founder than I expected. It makes such a big difference to have someone there to bounce idea's, make decisions together and just have the support of someone else who's just as involved and committed.
Very much agree with PG's statement that although possible as a single founder, you're chances of success are less.