There are two reasons why I love to hear this: "I will switch to linux when I can use [specialized piece of software]."
The first reason is: if there isn't already a free software clone of the latest version of what you want, then a virtual machine or emulation layer will do the trick. This is the technical argument, and works well on certain people.
The second reason and better reason is: it tells me that the person knows of 'the third option', they just...
