I would like this post to be a compilation for the FAQ of what is off-topic for this Web Apps site. With the purpose to prevent a lot of discussion early on, about what we do or don't want to see. Off course, the community has to decide what it should be, but it does make a difference if the early examples leave out things we would want to be off-topic!
For me there are several grey areas and points to discuss:
What makes a website a Web App? Is IMDB also a Web App? Or is basically any website in essence a Web App?
If the Triology is a Web App, should questions be asked here or on Meta.Stackoverflow.com?
Are questions about Web Apps or their interface? Examples: How do I download pics from Picasa Web Albums to Picasa desktop? Why doesn't Youtube play any video's under Internet Explorer 6? Why doesn't Hulu Plus work on my Android phone?
When do you stop being a Web Apps user (SU) and become a Web Master (SF)? Examples: How do I add social features to my Wordpress blog? How do I prevent spam on my Windows Live blog? How do I backup my Blogger blog? How do I change the background color of my blog?
What to do with legal question, such as: Is it legal to use Grooveshark? Is it illegal to visit the Pirate Bay?