First of all, the AT&T data is a bit wonky. This is unsurprising, as the iPhone service at my house is a bit wonky, especially as AT&T appears to have a lost a tower in my neighborhood sometime in the past few weeks and not yet gotten it back to service. On either device, I can watch the signal drop from 5 bars to 'Seeking' and back up to 5 bars without me touching a thing. This does not match my understanding of the behavior of cellular networks, unless the tower is dumping inactive connections to service other users.
That being said, 98% of my usage is at home, where WiFi applies. That has its own issues, as Comcast does something to the network every morning around 5 or 6 am, and occasionally substitutes carrier pigeons for IP packets during the day. I live next door to a small apartment complex, so possibly some script kiddies over there get periodically frisky and flood the data pipes in my neighborhood. Not the fault of the device, in any case.
I have yet to use the iPad 3G as a general reader, as Tobias Buckell has done, but that is coming soon. I'm looking forward to doing so. Unlike Toby, I've never found the iPhone a satisfactory e-reader, due to the screen size. I just want a bit more real estate. I'll review the iPad 3G on that basis when time permits.
At this point, I have two other comments which don't quite rise to the level of quibbles, but definitely color my view of the iPad 3G as a device so far.
One, the need to tether it to an iTunes installation really limits the market and deployment. Mother of the Child would be the perfect target market for this device, in terms of usability, but her interest in dealing with iTunes sync and maintaining a desktop computer simply to keep an iPad going would be somewhere south of nil. I recognize this is a constraint built into the iPhone/iPad OS, and I presume we'll see some form of 'cloud syncing' in the not-too-distant future, for those that simply don't want to deal with iTunes locally.
Two, I myself continue confused at fingertip level whether this is a iPhone replacement, a MacBook Pro replacement, or something in between. The last, obviously, when considered logically, but my inner user user hasn't made up his mind yet. I really like the email interface on the iPad 3G a lot, for example, better than either of the other two devices in some ways. On the other hand, the browser limitations cripple the functionality for me in ways that continue to surprise me.
I stand by what I said before. It will take me a few months to sort out how to live with the iPad 3G, and some of what I discover will doubtless surprise me over time. I continue to be quite pleased with it, and am having a lot of fun.
One last note, I am having a few recurring sync problems similar to what was diagnosed as being a bad USB cable. Given the age and distribution of USB iPhone sync cables around here this may well still be the case. I need to do a little elimination testing, after marking and labeling the cables, before drawing any further conclusions. That in return will require my brain to defog a bit more from the most recent chemotheraphy episode.
For now, iPad 3G win continues.