It's all the rage these days for Pro Photographers to 'slum it with the masses' and use iPhones. Generally I'm wary as a percentage of these stories are based around self promotion.
One thing it does prove it that people who want to get in to photography don't need DSLR's.
Or sometimes professionals don't want to have an SLR strapped around their neck--along with all the equipment to go with it--every time they're out and about. A decent camera on your phone that you carry with you anyway is a great way to still be able to capture a picture in an unexpected situation.