Hi Jackie
I think it's based on whatever you're most comfortable with - certainly a friendly face will make people feel more at ease with the whole concept of working virtually...just knowing that you are in fact a real, smiling, person might very well make the difference for someone who isn't used to the concept or still really likes the idea of real human interactions in this virtual world.
I think whatever you can do to show how personable, approachable, friendly, etc. you are the better for your business!

Black and white is great, love the artsy-ness of it! Good idea, to be sure. But, you don't really need to hire someone to take professional photos unless you really want to. What about using a good digital photo of yourself that you already have and like and just editing it in a program like photoshop to show in b&w instead of color? (much cheaper than paying a photog - unless it's the darling husband who will play lenscatcher for you? )

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