I'm in two minds, but I think I lean largely towards the notion that people can do whatever the hell they want to themselves, as long as it actually is only to themselves. If it's proven that the effects from Vaping/ECigs/whatever they are can actually be harmful to others than yes we should be looking at banning it in the same way ciggarettes are.Sure they might not look like cigarettes but you can still see the likeness when someone is holding it like a cigarette and puffing on it incessantly.
By not restricting there use in public, regardless of a lack of health concern, we risk normalizing this image of using eCigarettes, when really it should only be seen as a safer of two evils for people with an outstanding nicotine addiction.
I'm all for greater regulation on there use, and especially restriction on advertising and on all these paraphernalia shops I see popping up everywhere.
My company hasn't made any policy on it yet, but to be honest someone sitting at their desk puffing away would seem unprofessional to me.