It stinks even more when Apple adds new built-in functionality that competes with your existing application and you are notified that your application is no more. In fact, the more successful your application, the greater the chances Apple will decide to make it part of the OS.
Examples: * Coverflow(first standalone app by a developper) was bought by Apple. * The new iTunes visualizer was also first developped and then bought by Apple.
We'll see how Apple handles it with the iPhone
For example: Watson (http://www.karelia.com/watson/), was killed by Apple's Sherlock. Later, SandVox (http://www.karelia.com/sandvox/) was later followed up by Apple's iWeb. The list goes on...
Indie Mac developers have taken to calling this act, "Sherlocking". See a mainstream usage of the term here: http://blogs.zdnet.com/Apple/?p=1137
So, Apple swings both ways. :)