Activation seems to have become the bottleneck for the iPhone rollout...and that is largely out of Apple's control. I can see both sides, and there are several factors that effect things.
If I am an existing AT&T customer, getting a new number, and my current plan has no "special" riders then activation seems to go relatively well considering the number of people trying to activate their phones.
If I an NOT an existing AT&T customer, then a credit check is made (a fairly standard practice), and that throws a delay in. Now AT&T probably uses one of the standard credit reporting agencies for the check, and the problem may be at that end. Remember this crunch is a short lived thing, so Equifax, et al is not going to have added capacity at the cost of several hundred thousand dollars (minimum of you include purchase, installation, setup, testing, etc) for a few days of max capacity.
If you have any AT&T plan that requires a modification, that muddies the water more since that probably requires someone to enter the information by hand.
If you are transferring an existing number, or (heaven forbid) transferring from a different carrier, the delays may well be beyond the control of Apple or AT&T. If one were a conspiracy theorist, one would question if Verizon, etc were really putting in their "all" to help transfer accounts and phone numbers over to a competitor? Some discontent with AT&T certainly would not hurt "their" business...uuhhhmmmmm.
Shall I throw in one more monkey wrench...the long 4th of July Holiday is THIS weekend. Common IT practice is to schedule upgrades, major maintenance, etc for a LONG holiday weekend (we always use XMAS and New Years). Anyone want to take bets that one or more of the applicable interconnect parties in this operation did NOT schedule something for the weekend that is having a detrimental effect on performance? The LEFT hand rarely knows what the RIGHT hand is doing in big IT establishments.
Oh, and let's not forget the current trend of outsourcing a lot of support/maintenance work to foreign countries like India or Pakistan. The people who are handling the updates to your customer records may not even be in this country, or on this time zone (I wonder if that is one reasons they scheduled the rollout for the odd time of 6PM????). This can also throw a snag into the system. The volume of traffic involved in this rollout may be saturating the foreign networks ( and support workers) as well, which are often less '"robust" than those locally in the US. Again, no one is going to have increased capacity ( other than a few temp hires) for a short lived saturation.
I like the TV interview they did with the young video games tester...he wasn't going to get one until V2...AFTER they had worked all the bugs out! Young .....but with several lifetimes of "real world experience" ........