Hope this helps someone else:
I called AT&T regular customer support and bitched about our service. I've done this multiple times over the last two years. Sometimes they credit 50% of my monthly bill back, but spending 30 minutes on the phone is no fun. The gal says that she sees the record of this on her computer. I say I have a large house. She says she can send mail two of them to put in opposite sides of the house.
Well about three days later the Fedex truck shows up with FOUR microcells. I look at my bill and see no charge for any of them.
I go to
www.att.com/3dmicrocell and the site is down for maintenance. After a few false starts when it comes up, I'm able to enter the serial number and add four of my friends who all have AT&T on various phones.
Plug in the microcell into my Time Capsule and the lights blink for about twenty minutes. Then I get a text message saying WELCOME! MICROCELL ACTIVATION COMPLETE.
My iphone4 immediately picks up the new signal with six bars, but my wife has to powercycle her phone. (Not sure if she just waited a few more minutes if it would have picked up the microcell).
The Microcell range seems the same as my Time Capsule. My upload speed on my Cox connection is a crappy 70KB/sec but the quality seems fine. I couldn't detect lag/latency in the connection.
The worst signal strength I get is 3 bars in the farthest part of my house, but it never goes down or loses connection like it did before.
So I'm pretty happy and now wonder what to do with the three extra microcells they sent me.