1. The condition of a computer as a result of any one of an array of issues surrounding Windows Vista, including:
rejections of drivers, flaws in security, drops in performance/frame rates, legitimate media blocked by anti-piracy protection and software compatibility problems. Has evolved to encompass any 'improvement' or overhaul of a piece of software or updated interface that degrades utility and performance.
2. A sexual disorder primarily affecting top Microsoft management as a result of career dysfunction.
Fuck me... my fucking laptop has Vistitis. Now I have to install a p1rated version of XP.
Girl: What do you want me to do with that? It's got micro- soft Vistitis.
Executive: Julie at the office left me for Google today, so you will shut up and swallow my pitiful benefits package.