I got a nice bit of traffic from killerstartups as well (800some referrals I think). Before submitting there, one should figure out when their busy days are, when they seem to have slow days, etc.; my startup unfortunately got placed into a second page early on for their daily reviews and it stayed there most of that day.
Also, despite their audience, I didn't receive a lot of feedback initially. That took some more time.
I actually got about 200+ referrals from them, which was nice. In addition to multiple PR offerings.