Well I suppose that is an interesting idea but there are some details that i don't understand.
Why do I have to upload files? Isn't faster so speak and get the result real-time like Google does?
If you want this project to became popular, according to me, you should consider that there are still a lot of people which don't have access to a fast adsl (or optic fiber). For those people, uploading big files can be an incredibly onerous and long operation to be performed.