I've been a GNU/Linux user for about 6 years.
It's hard to migrate at first, I had a dream when I was younger that I would let my imagination go wild and create some cool Flash movies.
Unfortunately Adobe Flash is a no no inside Linux, it runs in WINE but the stability isn't so good.
I found a great alternative though, called 'Pencil' which is great for animating over vectors.
Another thing I missed was gaming too, but you can get basically anything running in Linux with a few tweaks, for example, I wanted to run my favourite point and click game called "The Longest Journey" I had the official CD but it would not run in
any Wine version as there was a problem with the shading, so I studied deep into Google for days, found the solution that several contributers of Wine released Patches, I compiled a Wine prefix, added the patches and the game works perfect.
Another game that I love is World of Warcraft, this runs in almost any Wine version with no edits/tweaks.
Linux is all about Trial and error, but it's fun and you'll gain a huge achievement of accomplishment.
Also, I'd like to add, In all the 6 years of running Linux, I've had none, zero, nada viruses at all, and only 2 kernel panics.
In Windows, I had 5+ BSOD in the first month I used it!
Hope this helps