What high-end applications are your referring to, fafalone?
Here are some reasons why I use and voted for Linux:
It's free.
Basically every application for it is equally free.
It has an empirical record of being more secure, a saner security model, and a community and philosophy more encouraging to quick fixes (and fixes at all).
If there's a feature I'd like in an application, I can (and often do) add it myself.
It has a decent cross-protocol IM application (gaim).
It has lots more and better development tools.
I dig bash.
The package systems of the distributions I use (Gentoo and Debian) are just amazing. Windows applications are always compiled for generic x86 processors, whereas Gentoo's package system compiles everything automatically with a bunch of optimization settings which make the binaries processor-specific in trade for speed. In Debian, I can open aptitude and update applications with the press of a button and install new ones equally easily.
The font rendering in GTK 2 is just amazing.
GTK2 and the UNIX API is much cleaner and generally better than the horrible Win32 API, which makes programming more fun.
Irssi is sex.
Mplayer is even sexier.
GNOME dockapps are really convenient.
Mutt is the best e-mail client I've ever used.
I love the freedom of choice. I'm currently a fan of GNOME2, but I used to love pwm. My requirements change, and with Linux, my applications follow accordingly.
I can run it without a monitor, keyboard, or mouse.
Its video interface, V4L, doesn't such quite as much as DirectShow (specifically, it has mmap capabilities); ever wonder why Dscaler has to run in ring-0, and why your video card has to be specifically supported by it? It's because DS is unusable.
WINE runs Half-Life more efficiently than Windows.
There's a lot more, including like 50,000 small subtle differences that together make me like Linux more, but I'm too lazy to type them all out.