Well said Jay. To clear up a couple misconceptions as well...
1. ALL "childcare" centers have to be state certified as do the workers. (Finger prints, background checks etc) Don't just take word for it, ask for creds on home based centers. People lie. You can easily call the state as well and find out for yourself a TON of information such as "incident" reports.
2. ALL centers/homes and/or classrooms have student to teacher ratios. If you are out of ratio, you get hammered by the state. (Same for leaving a child unattended. BH for instance has a zero tollerance policy on leaving a child unattended...even for 10 seconds. They get fired.) This ratio is usually higher for a home based center. This is determined by the STATE and not at the "owners" whim.
3. Also be aware that most corporate centers are what's called "self reporting". In otherwords, they report any and all things they know to be a violation of a state mandate. I.E. Leaving a child unattended. The directors have no choice, it's corporate policy. The state then comes and does an investigation on the report. That IMHO leave a nice paper trail for a center regarding incidents. Centers that are NOT self reporting leave it up to the state to "find out".
Home based centers CAN be good, but you really really really have to know and/or be sure about it and trust me, without being a "pro" just by walking in you have no idea what you are looking at or for. I am amazed when my wife walks into a foreign center (Went "center shopping" for the nephew who could not be in her place) and she just starts pointing things out left and right that are "wrong" against "state code" or just not very well done.
It's a very very sick world out there. IMHO the corporate centers have a much higher operational safety net than someone in their home.
My wife has been in the industry for 15 years, and a director for almost 9 in both private owned and corporate centers with a degree in Early Childhood Education. She is one of the best in her field and was in fact hired to turn her current center around - and it's become one of the tops in it's respective "region" that includes a very large geographical area up to the Boston area.
In proxy I have learned a lot myself and am simply AMAZED at some of the questions and/or reasons people choose one center over another. Things like the adults bathroom being out of toilet paper.
If you all would like some tips, I'll ask my wife if she'd be interested in making a "top 5 list" of "good" and "bad" things to look for in a center.
Oh and as for children being bitten...it happens. It's a part of life. Kids do that. It's not about supervision or "quality" of care when that happens. The parents on both ends of the spectrum feel terrible when it does.
They are going to get a lot more than a "nip" in life. You can't shield them from everything.