I agree with a lot of the information above - it is important to remember that ASP type software is not for everyone. My DSL can be very sporadic and in a rural community it may not get fixed fast. I really want to be able to operate even if my DSL or fiberoptic line is down.
For some people the Cloud is a neat idea - a single provider in the city or one who does house/nursing home calls might really like this.
As far as Linux goes - I think it would require too much work for the technology impaired. I think it is probably cool if you like to fool around "under the hood".