Found this interesting w/ little tips to remember when you check out a place.
Loved the one about watching the other children and seeing how comfortable they are there- and if they are happy.

MOM GUIDE
Who's Watching Your Child?

How to keep her safe, at daycare or with a sitter

Choosing a daycare: Before you decide
Get independent verification. Double-check all the info a daycare provider gives you. If the center is licensed, call the state bureau to make sure the license is current and ask about past complaints. If the provider says she's accredited, make sure it’s true. Lack of accreditation needn't be a deal breaker; many small, home-based caregivers don't bother. But it means you have one safety check fewer, so do some extra sleuthing. Check references, and not just the ones you're handed.

Take a good look around. Noticing details can help you make an informed decision. Is there plenty of room for kids to move around? Do you see workers washing their hands? What about smoke alarms and safety gates? Don't assume a perfectly neat room means a well-run operation. Kids should look comfortable just being kids, and that includes making messes. Find out the number of staffers. Experts recommend one adult to every four babies; two adults in a class of up to 18 2- and 3-year-olds


How to keep your child safe
Join forces with other parents. Many pairs of eyes are always better than one. Take turns dropping by unannounced during lunch or arriving early for pickup.
Listen to your child. Encourage your toddler to tell you about her day. Try "What was your favorite/least favorite thing about today?" Watch her facial expressions. Out-of-the-ordinary behavior at home, such as tantrums or hitting, can signal a problem. Talk to the daycare provider first (has she noticed these problems?), but also talk to your pediatrician

Offer your support. Your sitter should know that you can be called at any time for any reason. If she knows she can reach out when she's stretched to the limit, your child will be safer.
Treat caregivers with respect. You don't need to be best friends, but learning more about who she is can help her feel like she matters. Always treat her like a professional.
Stay in the loop. Drop in unexpectedly. Urge neighbors, family, friends, and other parents to keep their eyes and ears open.

If good care goes bad...
Don't make or accept excuses. Always listen to your gut. If you sense something is off, deal with it immediately instead of explaining it away.
Craft a Plan B. As soon as you suspect a problem, get your child out of the situation at once. That means always having a safe temporary option (grandparent, neighbor, etc.). Make sure your Plan B provides the level of safety you wanted with Plan A.
Take a stand for all kids. If you pull your child from a daycare out of concern for his welfare, make it safe for the children left behind. File a report with your state's childcare licensing bureau, or go to law-enforcement authorities.