Yes Digger they are
However, you would need a "fail safe" way of proving it in a court or law if there was a case
The "poor man's copyright" of posting a CD to yourself is not great proof - I can think of lots of ways to fake this
"Digital" copyrighting (eg via websites etc.) is yet to be tested in a court of law so I would not solely rely on this method
There is also the risk the website will not be around for long if it is a new business (I think this has happened recently)
GISC offers an independent service using "hard copies" and a referencing system that they stand by so I think this is the method likely to give the best "peace of mind" if this is something you worry about
There are other ways of building up "proof" - eg uploading to this forum, sound cloud, YouTube etc. - however I am sure these can be "manipulated" so it remains to be seen if these methods "stand up" in court