I don't look at credit scores. I look at what makes up the credit score. I've had tenants with lots of doctor bills in collections from having a baby or an accident. That doesn't reflect as poorly as somebody with 7 unpaid cell phone bills even though they may both have the same low score. Some people got screwed by the housing market and had to do a short sale or lost their house to foreclosure and took a big credit hit. I've been renting to people like that for the last 3-4 years.
The market for my rentals is generally couples/families that make between $10-$12/hour each. They job-hop a lot and can easily find another job to replace their income so job history for more than a year isn't necessary for me. I prefer to see it, but if they can show me a long time of employment and no missing time, I won't hold it against them if everything else turns out ok.