Notice how all of the full images look sharp and nice but pay close attention to the detail of each cropped image. Also notice the color of the iPhone Photos compared to the Canon 5D Mark II DSLR.
Notice how this image is blurry because it was hand held. This is a common problem with camera phone problems because it's very difficult to hold the camera still. Also notice that the image is starting to pixelate with rough edges.
To give the iPhone a fair chance at competing, it was put on a tripod with a special iPhone Tripod Mount. Again, the full image looks sharp.
On this cropped in image, it is sharper due to the tripod, but you can still see pixelation creeping in and the color still is not that great.
Now with a professional high quality camera, the color is what it should be, the image is very sharp.
Even when cropped in heavily as was done in the iPhone Photos, you can see that the image is still very sharp, the colors look good and there is no apparent pixelation going on.
A final note. While equipment is important, how that equipment is used is also very important as well. Proper use of equipment by a trained photographer is going to yield the best possible images and prints. And to answer a very common questions, "No, you can't always fix problems with an image in Photoshop". In fact, you can actually make and image look worse when enlarged or printed if you don't start with a good image and over do processing in photoshop.
The best images and prints are produced by using the proper equipment and get as much right on the camera as possible! Have fun with your camera or camera phone, but if you aren't trained as a photographer, hire someone that is for the important photo events!