I respectfully ask you to decide for yourself.
From real-life test that you can read about here, which I believe better reflects "normal" usage: http://www.anandtech.com/printarticle.aspx?i=3036
"The same can't be said about Wi-Fi vs. EDGE on the iPhone where there's about a 25% increase in battery life when we ran the test over Wi-Fi instead of EDGE; the difference is identical to what we saw in the web browsing test. It appears that maintaining the Wi-Fi connection and using it to periodically check for email is significantly more power efficient than doing so over EDGE, despite the reduction in data traffic compared to our web browsing test.
It seems to be that how much data you send isn't the only limiting factor, but rather just polling for new data is much more power efficient over Wi-Fi."