goodroi - 3:02 pm on Jan 15, 2013 (gmt 0)
I do not do any ecommerce which may probably change my opinion on the smallest devices.
I was a bit surprised to find my mobile users converted at nearly the same rate as desktop users when using my main sites (non-mobile optimized). Also I have seen a large number of mobile users prefer main sites vs. the mobile versions. It is making me think that mobile optimized sites aren't as necessary as I once thought.
Of course every situation is different so you may have different results for your keywords/industries.