That depends on how easy it is to do the jailbreak. If you can package a self-contained solution, or provide simple to follow instructions, the word will spread, and a lot of people will be doing it.
When I was buying my Paperwhite, I just ordered the ad-free version from amazon (.com or .co.uk, don't remember which). And then a couple co-workers (agreed, computer people, but very much not the type that's into tinkering or cracking software) looked at me with surprise, because it turns out everyone does the "standard" route - order "special offers" from amazon.de, and save money while getting an ad-free Kindle, because AFAIR initially the special offers didn't even display in Poland, and when they did, apparently everyone knew how to jump some hoops to get rid of them.
