According to mobile ad company InMobi, 41 percent of U.S. mobile users plan to buy the iPhone 5.

InMobi questioned 1,086 users across an “even demographic split” and found that 50 percent of those planning to buy an iPhone 5 will do so within the first six months. PaidContent posits—based on this survey and others—there is pent-up demand for the iPhone 5. This coupled with Sprints 52 Million users being able to purchase the new phone could increase Apple’s overall market share.

If consumers put their money where their mouths are, these numbers could go a long way to bumping up Apple’s overall market share in the UK and the U.S.. According to figures from Kantar Worldpanel, in Q2 Apple had an 18.3 percent share of the UK smartphone market; another research group, comScore, puts it around 20 percent. If people follow through with their purchasing intent, InMobi says this share would go up to 40 percent. In the U.S., the market share would grow to 41 percent.

However, all these predictions are based on Apple releasing an iPhone 5. If Apple releases a marginal update in the form of an iPhone 4S, significantly fewer users claim they would purchase the new device. In the U.K. the number drops from nearly 40 percent of users to only 12 percent purchasing the phone. However, what is rather shocking is the number of current RIM users who will be willing to give up their BlackBerry for either an iPhone 5 (45 percent) or 4S (28 percent).

Apple’s announcement next week is the culmination a never ending waiting game. With each closing month—now day—researchers are seeing a drop in other kinds of mobile activity by users, in anticipation of the new iPhone launch. Mobile marketing company Fiksu found that during the month of August organic app downloads were down more than 30 percent compared to previous months. The theory is that users are holding off on purchases and downloads on their current devices before making the switch to Apple’s latest offering.

It’s rather amazing that the mere anticipation of product launch can have that large of an impact on user’s mobile activity. But, when nearly half of current mobile users are anticipating a new device, it makes sense that the effects would be palpable.