Some great advice already given - I would suspect your area may well have wait times.

Personally I would not worry if a center did not have a wait list though - different parents look for different things so it depends on your definition of 'good'. I know my two go to not a particularly popular one but I love it (I think may be unpopular because of a lot of non-English staff (someone did say to me oh that is the Indian one isn't it?) - but everyone there loves the children and to me that was the main thing I wanted (might be different when you start looking for a 3 year old but for me for a 12 month old at the time affection was very important) - and as someone else said there are places where staff don't actually appear to like children let alone feel affectionate towards them. It has low core staff turnover, which I think is a good reflection of center also as if staff happy children happy etc (Staff who looked after DD in baby room are still there and now looking after DS)

Another key factor for me was ability for either DH or I to do pick and drop off - which means had to be easy to walk to from home and public transport. When I was working this was particularly important but also when I was home with DS was great that I didn't have to get out to do pick up at the end of the day too.

I also only looked at two - selected because I knew people who were happy with them - I would have been happy with either (the one I got I liked the amount of light better - and is open all year round apart from public holidays - the other was the council one which is cheapest and 300 metres away but very hard to get a place at and is shut in January for holidays and some other times - as we have no other family around for childcare going there would have forced us into holidays at set times). I figured at end of day they would go where I could get a place and I wasn't bothered enough to go on the waiting list and pay to be on list (sometimes you have to pay to be on list say $20) at 5 places when at end of day I wouldn't get a choice because places are few and far between.

I didn't ask a lot of questions, do research or spend any real time deliberating - just went on gut feel at look round and the fact that friends children were happy there. Apparently it follows The Reggio Emilia approach a fact I only became aware of recently - (after DD being at center 2 years!) - but I am quite a hands off parent when children are not with me and as long as the children looked happy I wasn't really fussed about anything else.

Once you are on wait lists is definitely worth keeping ringing up to check where you are etc, as they seem to operate by some sort of black magic with little logic behind allocation of places (probably because most people are on wait lists at 5 centers so keeping them current is a big job)