Branding is serious business and should be approached with a plan in mind.
Here is an interesting seminar on branding, customer involvement [feedback, recommendations], consistent imaging / branding across all medias, strong content helps brands, finding unique position to differentiate from competitors,
This is worthwhile information, about 50 minutes and will give you great thoughts on using images. You can skip the first 3:30 minutes to get to the presentation. The presentation and case study are in the first 35 minutes and then they take questions.