There’s an interesting (but rather short) interview with Cameron Neylon and Jean-Claude Bradley on the topic of open notebooks and sharing of data on the web. Some interesting points are made by both interviewees such as Cameron’s point on the main concerns:
The main issue is the fear of rivals stealing data. The second one is: will I be able to publish? And that depends on the publisher. Most publishers regard what we do as the equivalent of presenting at a conference, or a preprint. That hasn’t been tested across a wide range of publishers, and there’s at least one — the American Chemical Society — that doesn’t allow prepublication in any form whatsoever. There’s also a legitimate concern that a lot of people will put out a lot of rubbish.
And JC Bradley’s view of an open notebook:
The basic philosophy of open-notebook science is to have no insider information. Essentially all the information that is available to the [research] group is available to the rest of the world. You have an objective, a procedure and a log section, in which you report what you actually do.
These is far more to be said about sharing data and the use of open notebooks. Both Cameron and JC Bradley have written about their experiences on their blogs. I’d recommend snooping around because there is much to read.