Technology allows you to create almost any photo composition. Professional use PhotoShop, but you can get some pretty good results in PowerPoint as well. As with many technology tools, the fact that they are available does not mean you have to use them. 
Photo compositions that are "blunt" are more likely to invite a laugh from your audience than help you make a serious point. My opinion. What do people think? (McCow taken from Ads of the World)
For some great Photoshop creative work check out
(This post-flood New York image by Mandrak)

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