4S battery drains while plugged in

This is odd, I had my 4S plugged in/charging while I was talking. When I was finished with my 20-30 or so minute phone call my battery had gone down from 100% to 94%. And even stranger, when I was finished the green battery logo had the "plugged in" plug symbol on it rather than the "charging" electric symbol. Based on previous iPhones I understood that when it was plugged in with the battery under 100% it would be charging and would show the "charging" symbol on the battery logo, until it reached 100% and then, if still plugged in, it would show the "plug" symbol to indicate it was getting external power. You'd never see the plug symbol on the battery when it was under 100%.

I unplugged my phone and quickly plugged it back in, and the symbol changed from plugged to charging (it was 94% so it should be charging).

None of my prior iphones would drain the battery when I talked or otherwise used the phone while it was plugged in. I could talk for 30 minutes on my 3GS and the battery would only go down 3-4%. Even if the battery on the iPhone 4S is going to remain crappy, I certainly don't expect it to drain while it's plugged in. I should be able to talk on speakerphone at the loudest volume while running all the background apps I have for an unlimited amount of time with it plugged in.

I love the new 4S but I'm really not happy about the battery life issue, the bluetooth siri startup freeze, and now this. Am I the only one whose battery drains while the phone is plugged in?

thanks