This is, to me, a shocking statement for a working photographer to make. Its just like gr said, if your not using flash its cause you aren't comfortable with it. Flash can enhance an image in any lighting condition. Given a remote trigger, some very simple modifiers and a little patience you can really create looks not possible any other way. And most importantly for a wedding photographer, you can create an image that no guest will have the ability to duplicate which translates to more sales on the back end.
Here are two recent examples which immediately come to mind. In the first image my brother was looking for an image to send out with his graduation notices. The the lighting was even and warm. I could shoot with the sun at my back and easily illuminate the subject. I could also turn the subject so his back is to the sun (using it for a hair light) and fire a Nikon SB-600 into an umbrella which would provide a more controllable key light while still looking natural. The result is a great look with a VERY simple set-up.
This second image is much the same. I could have easily shot with available light and gotten good dynamic light with the low setting sun. But I also knew I could use the same flash into the same umbrella and use the sun filtering through the trees to create a soft bokeh-filled background.
Shameless plug: I am selling my SB-600 (the very one used to make both of the above shots) on eBay. It comes with the flash, Nikon color correction gels, rechargeable batteries and charger, and RF wireless remote triggers. There are 36(!) watchers with less than 23 hours remaining. Here's the link: http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&ssPageName=STRK:MESELX:IT&item=270266431120
There's other camera gear too but I don't want this post to get deleted for violating some linking rule.
But yea, I would love to get better at it.
