Ask professional photographers about equipment and most will tell you the same thing - its not the equipment that makes a photographer good.
This is true, however there are some situations where your equipment can help you get pictures that may not otherwise be possible.
The picture above was taken at Crondon Park Golf Club late in the day on a dark, wintry December afternoon with no natural light. The exposure was 1/125s at f1.2 at ISO3200. That's dark. Really dark.
There are two problems shooting in such low light. Firstly you have to get a good exposure, without camera shake. (The blur of the girl in this picture is due to her movement which I'm perfectly happy with). Secondly, the camera needs enough light to focus. Both of these problems can be overcome with the right equipment.
This was the first wedding I shot with the new Canon 5D Mark III. I'm not going to write a review of the camera. There are plenty of other places that have done that. What I will say is its a massive improvement over the original 5D and the 5D MkII in one significant way - the autofocus.
I don't think I could have shot this picture with anything other than the 5DIII. Even my previous, more expensive, 1D MkIV would have struggled. The 5D, in combination with the fast 85mm f1.2 lens has allowed me to get the exposure I needed for this picture, but also, crucially, has been able to accurately focus the lens even with the extremely shallow depth of field at f1.2.
After using the 5D MkIII at this wedding I bought another one. And sold both my 1D MkIV's. Its that good. And I haven't even mentioned that its small, light, very quiet and has amazing image quality.
So yes, having the right equipment does matter, but only in the hands of a photographer who knows what to do with it.
(You can see a full set of pictures from this wedding in the sample albums section here.)