Perriello is off to a good start but I still think Northam has the edge. Northam should no well in the economically centrist NOVA suburbs. I personally prefer Gillespie, but if a democrat is going to win, I'd rather have Perriello over Northam. Also think Northam is the stronger candidate since he can run up the margins in battleground NOVA.
Honestly, I think Perriello is starting to gain a lot of ground over Northam. A lot of the buzz surrounding this race is about the former rather than the latter.