I am fairly certain this is a bug and has been posted in other threads, but doesn't have its own thread.
The WiFi constantly searches for a new network even though it is connected to a network. This will compromise the battery life (I'm assuming). You can observe this by connecting to a WiFi network, then going into settings, Wireless and Network, WiFi and watching it scan and scan and scan.
I did verify that you are correct...this test device does the same thing. And this is not listed as a known issue. There are no settings to make it stop scanning...I am going to forward this issue. Hopefully we will have a patch that addresses this problem fast...I assume it will really run down the battery fast.
Take a look at a few other forums, many people are seeing this same issue....like on XDA there is about 11 pages worth of posts regarding this issue. The belief is that it is keeping the Android OS up and keeping the uptimes high on the phones and this causes a severe drain on the battery.
One temporary work around was to turn WiFi policy to "off when screen is off" then back to "never" after a little while. So I think that there is some sort of scanning bug going on with the WiFi, but I'm glad you're on it now!!!