The presence or absence of a copyright notice is theoretically irrelevant. This was done to conform with the requirements for visual arts, or audible arts for that matter, which don't require the artist to deface a work of art with a copyright notice. There's a move in the USA, on the other hand, to allow infringers to make use of copyrighted material with minimal damages available if they've made a "reasonable effort" to obtain a release for a particular use.

What does make a difference is registration. Without registration, one is limited to actual damages, which is very difficult to prove if one is giving it away for free, and attorney's fees may not be available. With registration, one may choose statutory damages rather than actual, although the amount of "statutory" damages may also be small is the work was originally distributed gratis. With registration, attorney's fees may be available as well. Notice may help to show the the infringement wasn't "innocent, " but it's easy to say that one found a copy on the Web with no notice attached, so the addition of a notice couldn't hurt, but probably won't help all that much either.

The reality is that copyright law is a game for those with deep pockets, and part-time writers are unlikely to be able to mount any serious case, unless one has enough ducks in a row, and an infringer with enough money that it would be worthwhile suing the infringer.

This is why the lawyers went after Napster, although they were relatively innocent third parties, and made only token efforts against the actual infringers, who were mostly young people with no assets to speak of. Napster had assets.

Big mistake. What they should have done was create a company which owned the assets, and then rented them to another company with at least nominally different management.

Cheers,

Liobhan