When my wife and I got married we checked out numerous photographers. The one we finally chose had a great website and really nice photos displayed there. We met with her a month prior and everything sounded good. Turns out she wasn't very good. I think she made herself look like she was very experienced and from the photos from previous places and people she looked the part. We were very disappointed in the service and photos. It's a once in a lifetime memory so make sure you know what you're getting. Referrals etc. Good luck. This is one place you need to make an educated decision or it will haunt the bride and groom.

As a wedding florist who solicits photos for promotional use, I have looked at hundred of thousands of wedding photos, perhaps millions, from dozens and dozens of photographers. Some of them are companies employing several shooters, others are small teams, couples, or solo artists.
DWU2 has given you a great list of questions for candidates, although I wouldn’t fuss too much about what equipment they use.
Check their websites, and get a sense of their style and feel. Break it down by category- prep, ceremony, formals, candids. Get a sense of what’s most important to you, and convey that to your candidates.
Our best clients come to us from referrals by other vendors. There are always instances where a couple brings in a photographer, caterer or band from out-of-state, but for the most part we all work with each other very frequently. Ask your other vendors for recommendations, and ask why they are recommending them.
Lastly, meet them in person and find out who you connect best with. And while you don’t want to micromanage them, be sure that they understand why you chose them and what you want.
Hopefully budget won’t be an issue!

Off the top of my head:
- Is our date available?
- How many weddings have you shot?
- How many have you shot in the past year?
- How many weddings do you work in a weekend?
- Can we see examples of your recent portfolios?
- What do your standard packages include?
- What are some common extra-cost items?
- How fast should we expect to see the proofs?
- How do you share the initial proofs?
- Can you provide several references?
- Do you shoot strictly digital, film, both?
- Do you have a published price list?
- Can you share your standard shot list?
- Are you the photographer who will shoot our wedding?
- Do you have a second (or third) photographer/ assistant and, if so, will the assistant be on our job?
- Who would cover for you if you got sick?
- How do you handle emotional and/or inebriated guests? Children?
- What was the hardest wedding you ever shot?
- What equipment do you use to shoot? To edit?
- What lighting equipment do you bring?
- Have you shot at my venue before?
- What's your policy on file sharing and ownership?
- What's your payment schedule?
- What do you shoot prior to and following the wedding?
- What if our event runs long? Costs?

There are some photographs that will really stand out when you are finally old enough to value things that matter in life. I've spent time with my aunts and uncles when they reach the age of 80 or more, and more often than not, their conversations involve getting me to look over old photographs and they ask me to copy them and to enlarge them so that they can see them better. I return the next weekend and they tell me the stories behind each photograph. As it turned out, those stories were not known to the family beforehand, and I am now considered the family historian because of my experience with the older generation. I am now 70 years old and have become that older generation.
Wedding photographs are often neglected when it comes to the old family photograph albums. This is because so few older folks had the money to spend on their wedding photos. Often there's only one that survives.
I would suggest that you look at old wedding photographs from your own family's history. Notice the ones that mean the most to you. These are probably the ones that include family members who are now gone. Perhaps they came from far away to attend the wedding, and many of the younger members did not often see them.
In this case, the group photos are important. If so, make sure that the photographer you hire can set up a group photo where everyone is in focus. Their faces are clearly shown and their expressions are all decent. In the old days, it was common to press the shutter just when someone in the group would blink. Nowadays, assuming the photographer is shooting digital, they can replace heads with the best expression for each individual. The photographer, in this case, exposes a number of shots of each set up and looks for the best expression of each person in the group and replaces certain head shots with ones from another exposure, thereby providing you with a group photo where everyone is decently represented.
These concerns are often those of the parents because the bride and groom are more interested in their wedding party and their close friends who will be attending. But it is my experience that in the long run, family rules. Friends come and go, but family is there for the long term. This scenario escapes the bride and groom until they reach the age of 50 or more. That's when family history becomes more important. It's when we begin to lose the older generation when we realize that we should have spent more time with them and listened to the stories of their lives.
For what it's worth, that's my recommendation. Make sure the photographer can capture meaningful group photos (along with the post processing work in photoshop) along with the current popular "candids" that are flooding the wedding market.