I concur: WiFi power usage has improved.
Power usage doesn't seem improved for me. With no SIM fitted and wifi enabled, my gemini went from 100% charge to dodo dead in less than 20hrs while sat on my desk unused.
I'm dissapointed, but I'm done wasting time on this device.
For comparison on Android I get a full day of moderate 4G and Wifi usage out of my Gemini with usually over 50% battery left at the end of the day. WiFi only and no use it would easily last more than 3 days so while I understand your frustration I would respectfully suggest the issue is the software rather than the device?
I get similar battery life to your Android from my Gemini using SF. I am not using push email and I tend to force close apps not in use, this may be the difference.
WiFi can affect battery if the signal is not solid. Also, batteries are not always the same over their lives. Depending on how they have been used, their ability to hold a charge can be damaged - I believe heat can be a problem here.