Personally I think that JK Rowling should cut a check to the people who scanned HP7 and posted it, since that story transformed a mega-mega event into a mega-mega-mega event in the publishing world, and most likely improved her sales by a significant fraction
The more general question about uploading/downloading books is very tricky in my opinion; I guess if you leave anywhere in the western world there is no way not to break some law or another, from jaywalking to traffic law, to tax law (for example anyone in the US buying the Sony Reader online tax free and not paying their state sales tax on it at tax time is breaking the law - not that your state income tax enforcement people are going to bother), and even considering that downloading or uploading is deliberate while sometimes you are not aware of this or that law, ignorance is not an excuse legally.
Maybe it's a good idea to break tax law but not break copyright law, but the issue is not that black and white.