I'm not a parent, but I worked in a daycare for three years and I can give you some input based on what we did with the kids we had. FYI, I was a head teacher in the infant room (12-18 month olds) for 2.5 of my years in daycare.
We were NAEYC accredited - you can find out more info on that by going to
www.naeyc.org and you can even search for NAEYC accredited schools.
Make sure the daycare center will give you a full tour - I recommend going at both "naptime" and either before or after so you can see the kids while they are sleeping (and what they sleep on) and you can see what their activities are for all age levels.
Ask to meet with the teacher your child would be assigned, go into that classroom, ask questions, etc.
See if they do lesson plans - and yes, at my center we were even required to do lesson plans for the 6wks-12 month olds. They weren't adhered to strictly, as each baby had their own schedule, but at least you can get an idea what kind of activities even the wee ones will be involved in throughout their day.
Make sure they fill out daily reports - chances are, the person you drop your child off with in the morning will not be the person you see at pick up and oftentimes they may or may not know exactly how little Timmy did throughout his whole day. The report will at the very least let you know how often Timmy was changed and fed and what his disposition was like during the day.
See what kind of formulas they provide and if you need to bring your own what kind of documentation you would need to bring it (prescription sometimes). For example, we had a couple of children that were on various different formulas for health reasons. If large numbers of babies needed the specific formula, the center would go ahead and order it and incorporate it into the system. Otherwise, the parents would have to provide it on their own.
I agree with what other posters said about ratios. The law in NJ required at the time a 1:4 ratio. I don't know if it's changed now, or what it is in your state, but you want to make sure they stick to the ratio.
Also check their sick policy. Ours was if the child had a fever of 100.5 or higher they had to remain home for 24 hours.
CPR/First Aid certs were required for at least one teacher in every classroom during operating hours.
See if they have a playground. If so, make sure the infants are separate from toddlers and preschoolers.
Make sure they have interesting toys to play with. Sometimes if a parent saw we were missing something they thought we should have, they donated it to the classroom. Also check to see if they have duplicate toys - this is important in classes with large amounts of children.
That's basically all I can think of for now. If I think of more, I'll add to it. HTH!