My biggest advice first: get on waiting lists now, even if you don't need them at the moment, you never know what will happen later...
We had a horrible time with childcare for my son...we knew we were moving about 3 months after he was supposed to be born (yeah, not how that worked out either, but a separate story) and because my husband and I both have crazy schedules we decided to get a nanny at first and then planned to do daycare when he was one or so. Since we were moving to a new place, we went with a nanny agency because we figured that would be easier and would help filter out any truly horrible ones. Well, the first nanny was a disaster and it took way too long to find a replacement. She ended up staying with us for 3 months and by the end, I came home every day to a screaming baby. She'd say things like "you need to take him to a doctor to figure out what's wrong with him", she wouldn't take him outside for walks because he was "too fussy" even though being outside always calmed him down, I'm pretty sure she was also stealing household supplies like dish soap and toilet paper, etc..... I still feel guilty that she was the one with him for that long.
The second nanny was great, it was literally a complete change from one day to the next (we fired #1 on Monday and #2 started Tuesday). But we could only afford part-time care and right around when my son was turning one, another family offered her more money out of the blue so she left.
So we decided to go ahead and do daycare, since that had kind of been our plan anyway...but we only had a few weeks to find one. We found a spot at one that one of my coworkers had her children at and she liked them a lot, so I figured it would work out great. It seemed fine for the first month or so, then one day I picked him up with a soaking wet diaper on and he'd only had one change the entire day. A few days later, they charted on his daily sheet that they'd given him yogurt when he was listed as being allergic to dairy. When we asked the teacher about it, she said they just charted it wrong, but they didn't really give it to him (not a severe allergy, so who knows which was true). We spoke to the director who seemed horrified about both of these things....then the next week he came home with only one diaper change the whole day. We spoke to the director again. They did it again just 2 days later. We started looking for somewhere else...(ended up getting on several waiting lists at this point)
We finally ended up doing a nanny-share with one of my coworkers which worked out great. That lasted nearly a year, then the nanny decided she wanted to go back to school in the fall and wanted to spend the summer just with her kids. Here's where being on the waiting lists from before came in handy, because we were actually able to get a spot at another daycare right when we needed it at the beginning of the summer.
The next daycare was pretty good, we had no major complaints with them. My son ended up potty-training shortly after he turned 2 (and therefore shortly after he started this daycare), so that was at least one area we didn't have to worry about. Because of my job, I almost always picked him up after his regular teachers left, so I felt like I didn't have great communication with them, but really they worked out well. He ended up being there just over a year, until we moved again...
...and he started preschool in DC at the school where my sister is a teacher. So, really, we've been quite happy with them.
And that's where we are now. Well, he's doing "summer camp" at a different preschool but going back to my sister's school in the fall, so that will be by far the longest he's been with any one given person/place.
I'm a little worried about what's going to happen now that we're expecting #2 given the horrible experiences we had the first time. But we definitely gained a lot of experience in how to deal with issues and what not to put up with for any amount of time.