The multiple choices in the web world for connectivity

While I am trying to revive my activity in the blogospace,I am pulled in various directions by the other social networking options.Orkut,Myspace,Facebook,Twitter which one to focus.Right now I am exploring Twitter because it has been reported as the latest rage of 2009.Better to catch up with technology and innovation,even if it means changing platforms..or to dig deeper in the existing space and build the tempo of activit rather than catching up with the ever changing (is it evolving,no it is changing from one concept to another)...That remains the networking dilemma.