We've all had the problem: a desire to change products but a fear of the disruption. Why haven't you switched from wired phones to VOIP? Why aren't you on BaseCamp for projects and Google apps for email? Why are you still using <old_thing> instead of <new_thing>?
Answer: it's less the fear of change than the hassle of change. What we have now is working; the new thing requires learning the new way and figuring out how to move existing assets (files, data, configuration, workflows) to the new platform.
Apple has had this problem for years. Some people want to switch to Macintosh but, golly, all my files are on a PC. Does Mac have Word? How hard is it to understand the file system? Is the Mac compatible with <whatever> at work? That's why Apple offers the "Why you'll love a Mac" which assures you that it's easy to switch from Windows.
I love Posterous. This new (to me) service is simple; just email it to blog it. While some services require you to mess around with HTML, with Posterous, just email your post and forget it. Instead of a silly email address, it knows anything from your email address must be for your posterous blog. Nice! Oh, and then it autoposts to other blogs and social media. Super easy.
"But wait"--you say--"I already have a blog and all this great content on <something_else>!" No problem, go to http://posterous.com/switch/ and they'll move all your data too. Still not sure? Check http://switchto.posterous.com/ for success stories and see what other have to say about it. Oh, and what a great marketing message: Switch your site to the simplest publishing platform on the planet.
Many of our development plans focus on adding new functionality to win new deals, or upgrading functionality to help existing customers. But what about your competitor's customers? How can we help them? Do you want them to drop what they've been doing and switch to you? If "yes," make it a development and marketing priority. Make "Switch" a development and marketing theme for an entire release or series of releases. Develop tools to move their data, workflows, scripts, configurations. And create marketing programs to explain how easy you've made it to switch.
Now... how do I switch the house over to Ooma?