There could be fundamental differences among SCII players of different races (Random included), so this topic fascinates me. I found a few forum threads on BNet that ask the same question, but after 5 or so serious answers, those threads all devolve into the same interracial flaming that plagues most internet communities. "Toss is easy!" "BS, Zerg is easy!" "You're retarded!" "You're Gold so you don't know anything!" and blah blah blah.
Day's community is definitely a league above the rest in terms of civility, though, so I think this is a good way to learn more about this.
So, if you play mostly/exclusively Zerg, then why? If this thread gets serious, then I'll post about Terran, Toss and Random, too (unless someone else wants to throw those posts up first).