I think the Internet is a GREAT source of learning and information. It's also a great source of misinformation and can be an incredible waste of time (you can define what wasting time is
), but at the end of the day, it's just a tool to augment our lives and open up new possibilities.
It's what you make of it, and it does take a certain amount of discipline and effort to sift through some of the B.S., but on the whole (especially regarding diving) I've found that I have benefited greatly from the net. From being made aware of what's out there in terns of education, equipment, places to dive, articles of interest etc... as well as learning and seeing things from a different perspective from those with more experience (or any experience shared for that matter). It's also a great source for meeting some very cool people.
Definitely as far as I'm concerned it's been a good thing... but as always YMMV.