The brown-box replacements are not refurbished units, they are new units.
I am on my fourth, yes fourth, iPad 2.
I picked up the first one on launch day and waited 6-7 hours like everyone else.
After making 7-8 trips back and forth to the Apple store, and multiple calls to AppleCare I have been offered what I perceive to be an acceptable solution.
This fourth unit that I have is probably the best one I've had (although far from perfect). The proposed solution is to keep this one for as long as I want (6 months or so) until a fix is in place. I have a senior advisors direct line and he will replace the unit as soon as the "manufacturing defect" as he called it is worked out. In addition to letting me keep this one, and exchange it later, they are going to send me an iPad 2 case of my choice (up to $100 value) for free. After looking at 10+ iPad 2's today in the store, and noticing that all of them have this issue, I feel that this is the best solution for now.
At least I finally got someone at Apple to admit that it is a serious problem and that I would likely not find a "perfect" one until they fix the manufacturing problem. I am quite impressed with how they handled things today, as opposed to this past week. They nearly lost a customer.
My suggestion to you all is that you find one that is "acceptable" and then make sure that you document the issue with AppleCare and demand a replacement unit in the future. Make sure you get names and direct contact information, it helps.
Best of luck to the rest of you,
Ryland