Given my very vocal stance in recent weeks regarding the need for socialists in advanced countries to organize SPD-style (ie, revolutionaries and real, post-welfarist reformists), would a good start for unity revolve around "senatorial" organization for online and/or print newspapers?
For example, the editorial board would have one pareconist along the lines of Michael Albert, one "market socialist" along the lines of David Schweickart, one generic "democratic socialist" (but one who opposes mere "social democracy"), one liberation-theologist, one Trotskyist, one ortho-Marxist, one "maximalist" (revolutionary demands only, no minimums), one generic Marxist (preferrably a small-r revolutionary Marxist), and maybe even one anarcho-Marxist.