Assuming this is correct, would we expect that it's a temporary phase-over for people whose old plan hasn't yet expired, and they'll eventually move to just the iPhone?
Or are there really that many people who will continue to carry 2 phones, presumably because of tradeoffs between them?
Yeah, I question that one, too... I have two phones -- I have my Blackberry, still, but I have not turned it on since I got my iPhone working. In another week or two, I'll probably decide I'm comfortable and sell it.
When I got my BB, I kept my RAZR for a while, and occasionally used it, e.g. to avoid taking the bulky BB with me when I went out on dates, etc... but after a while, switching phones became a nuisance and I sold my RAZR.
I never really "carried" two phones.
There are people who actively use two phones, but I would be shocked if anywhere near 1/3 of all iPhone users "carry" a second phone with them.
Here's more from the PDF:
There have been anecdotal reports that some iPhone users also carry a second mobile phone for traditional voice calling, or for other functions the iPhone doesn't do well. The survey showed that two-thirds of iPhone users carry only a single phone.
Among the one-third of iPhone users who do carry another mobile phone, the RIM Blackberry was the most popular, carried by almost one iPhone user in ten. It's not clear what will happen to this statistic over time. As Apple adds Microsoft Exchange
compatibility to the iPhone, it's possible that some of the dual users will discard their Blackberries. On the other hand, the people carrying both may be doing so because they want to use the Blackberry's built-in keyboard to type messages, and Apple has
announced no plans for an iPhone with a keyboard
On the other hand, they report that 90% report replacing a phone with the iPhone... I'm not sure their respondents really understood these questions and what was meant by them.
Another interesting piece of data was that 13% of respondents reported unlocking their iPhones, and about 50% report adding applications. Although, again, it isn't clear if this means that 50% jailbroke their iPhones (skeptical) or this includes webapps....